JPH0939486A - Coordinates correction device in xy plotter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enhance workability by automating the reference coordinates correction work of a writing utensile in an XY plotter. SOLUTION: A video camera 8 is mounted on the head carriage 6 of an XY plotter side by side with a writing utensil 7 and image data is inputted to the image analyser of a control part. The image analyser searches the pattern coinciding with a crossed pattern for collation from the image data by matching function. When a reference coordinates three-point correction command is inputted, the control part drives the head carriage 6 to successively obtain coordinates data of the origin P0 of plotting paper 27, the rule intersecting point P1 on an X-axis and the rule intersecting point P2 on a Y-axis. The control part corrects the coordinates system of drawing data on the basis of the obtained three-point coordinates data and the plotting lines of the plotting paper 27 coincide with the coordinates system of a drawing.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an XY plotter, and more particularly to a coordinate correction device for an XY plotter.

[0002]

2. Description of the Related Art Conventionally, an X using a writing instrument such as a pencil
Some Y plotters have a coordinate correction function that corrects a mounting position error of a writing instrument mounted on the head carriage and a relative position error between a ruled line of graph paper and coordinates of drawing data.

In addition, when drawing a drawing having a size exceeding the drawable area on the drawing board, one page of long paper is fed for each drawing of the page so that the coordinate systems of the drawings on the preceding and following pages are made to coincide with each other. The coordinate correction function is used to continuously draw on one long sheet of paper.

In a general coordinate correction function, a user observes an image in a loupe mounted on a head carriage, and an XY plotter draws the intersection of a cross-shaped collimation mark provided on the loupe and a coordinate correction. The correction amount is calculated from the movement amount of the head carriage by matching the cross pattern or the intersection of the graph paper by operating the head carriage movement key, and the coordinate correction data is stored in the memory by the registration key operation. .

Further, the applicant of the present application mounts a video camera on the head carriage of the XY plotter, performs image processing on the image of the cross pattern for coordinate correction drawn on the drawing board, and performs the image processing on the cross pattern for correction and the reference by computer processing. There is proposed an XY plotter in which the deviation from the coordinates is obtained and the coordinate deviation due to the individual difference of the writing instrument is automatically corrected (Japanese Patent Application No. 6-140497).

[0006]

Conventionally, in order to make coordinate correction work for making the ruled lines of the graph paper coincide with the drawing coordinates when drawing on the graph paper, and to make the connection portion of the long drawing divided and drawn coincide. The coordinate correction work is performed by the user operating the keys on the operation panel, and the operation procedure is complicated, so there is a problem that the work efficiency is reduced. Therefore, there is a technical problem to be solved in order to save the correction data input work and improve the work efficiency, and the present invention aims to solve the above problem.

[0007]

DISCLOSURE OF THE INVENTION The present invention is proposed to achieve the above-mentioned object, and a video camera for photographing a drawing board surface is mounted on a writing instrument driving head carriage of an XY plotter, and an image is displayed on the screen. Control means for drawing a cross pattern, an image analysis device for detecting the center point of the cross pattern from the image data taken by the video camera, and a coordinate based on the amount of displacement between the center coordinates of the cross pattern and the reference coordinates of the imaging screen. In an XY plotter equipped with a calculation unit that calculates correction data and corrects the coordinate system of the drawing data, when drawing the drawing data of a size exceeding the drawing area into a plurality of pages, the vicinity of the last line of each page Control means for drawing a cross pattern at two points, and the head carriage is moved to the vicinity of the start line of the drawing area at the start of the drawing on the next page, and the cross is made by the video camera. An XY plotter comprising: a control means for automatically searching for a turn; and a computing means for correcting the coordinate system of the drawing data on the next page based on the detected center coordinates of the two-point cross pattern. The present invention provides a coordinate correction device.

Further, the head carriage is driven in response to a command, and the video camera and the image analysis device are used to determine the origin of the grid pattern on the drawing board on the XY axis, the ruled line intersection on the X axis, and the ruled line intersection on the Y axis. A coordinate correction device for an XY plotter, which is provided with control means for automatically searching for three points and control means for correcting the coordinate system of the drawing data based on the detected coordinates of the three points. It is provided.

In the case of drawing a drawing having a size larger than the drawable area, after drawing the drawable area, a two-point cross pattern is drawn on the screen connecting portion at the rear end portion of the drawable area. Terminates the screen processing. Next, when the operator sends the drawing paper and positions the two cross pattern drawing areas that are the reference points for screen connection at the front end of the drawing area on the drawing board and inputs a drawing restart command, the head carriage draws the drawing area. It moves to the vicinity of the front end part of the image and sequentially searches for two cross patterns from the image of the video camera, and calculates the coordinate data of the detected cross pattern. The control unit corrects the coordinate system of the second screen based on the coordinates of the two cross patterns, and executes drawing. Therefore, regardless of the displacement of the reference coordinates due to the movement of the paper, there is no disturbance in the connecting portion between the first screen and the second screen, and the drawing result in which the coordinate systems match can be obtained.

When the coordinate correction for the graph paper is performed, when the execution command of the reference coordinate three-point correction is input, the head carriage moves to the vicinity of the origin of the drawing board, and the origin of the graph paper is searched through the video camera. Get coordinate data. Hereinafter, the coordinate data of the ruled line intersections on the X axis and the ruled line intersections on the Y axis of the drawing area are sequentially acquired, and the coordinate correction of the drawing data is executed based on the acquired coordinate data of the three points.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, an example of an embodiment of the present invention will be described in detail with reference to the drawings. As shown in FIGS. 1 and 2, X
Horizontal rails 3 and 4 are provided at both front and rear ends of the drawing plate 2 of the Y plotter 1.
The vertical rails 5 are installed on the horizontal carriages (not shown) mounted on the horizontal rails 3 and 4, respectively. A head carriage 6 is engaged with the vertical rails 5, and a pen head (not shown) is mounted inside the cover of the head carriage 6 so as to be able to move up and down through a moving coil actuator, and a writing tool 7 such as an ink pen or a pencil is attached to the pen head. It is installed. A small CCD black-and-white video camera 8 is mounted on the head carriage 6 along with the writing instrument 7 so as to face the drawing board surface. Has been done.

FIG. 3 shows the configuration of the XY plotter 1, and the video camera 8 is a video signal input device 1 of the plotter controller 9.
0, and the video signal is written into the frame memory 12 via the input / output control device 11 after being subjected to sampling, binarization by A / D conversion, and noise removal processing by the video signal input device 10.

The drawing data input from the host computer 13 to the buffer memory 15 via the interface 14 is expanded into vector data by the data processing unit of the CPU 16 according to the drawing program of the ROM 17, and the generated vector data is stored in the data memory 18. Write.

At the time of drawing, the CPU 16 reads the vector data from the data memory 18 and the X-axis servo circuit 1
9, the Y-axis servo circuit 20 and the Z-axis servo circuit 21 are driven, and the X-axis motor 22, the Y-axis motor 23, and the Z-axis drive coil 24 of the moving coil actuator are feedback-controlled to create a drawing according to the drawing data. It

In the ROM 17, a writing tool error correction program for correcting the individual difference of the pen tip position of the writing tool and a coordinate system of drawings continuous over two or more screens are made to coincide with each other and expressed as a series of drawings on a long sheet. There are stored three types of coordinate correction programs, namely, a connection coordinate correction program and a standard coordinate three-point correction program for ruled lines of graph paper.

When executing these coordinate correction programs, the video camera 8 is activated, and the CPU 16 controls the X-axis servo circuit 19 and the Y-axis servo circuit 20 in accordance with the coordinate correction program to move the head carriage 6 to the target point. Then, the image analysis device 25 searches for the target pattern. The image analysis device 25 has a pattern matching function, and detects a target pattern by a cross pattern for matching given in advance.

The position of the pen tip relative to the head carriage 6
When correcting the error, the writing tool error correction execution command
The head carriage 6 moves to the target point and the video camera
Position 8 directly above the target point and stop it.
As shown, the image taken by the video camera 8 at the target point
It is written in the frame memory 12 as image data.
Then, as shown in FIG. 4B, the image analysis device 25
Cross pattern P for matching _refA pattern that matches
The image data in the memory 12 is searched.

As shown in FIG. 4C, when the matching cross pattern P _ref is scanned and a matching pattern P + is detected, as shown in FIG. The displacement amounts Δx and Δy between the reference origin C ₀ and the center coordinates of the detection pattern P + are calculated, and the obtained writing instrument coordinate correction data is stored in the data memory 18. CPU
Reference numeral 16 corrects the coordinate system of the drawing data in the data memory 18 based on the coordinate correction data when executing the drawing.

When dividing a drawing having a size larger than the drawing-enabled area and drawing the image, the CPU 16 determines whether or not the connection coordinate correction processing is necessary from the drawing size of the input drawing data, and
As shown in (a), the drawing of the area where the drawing is possible is executed and the drawing is interrupted, and as shown in FIG. 1B, the vicinity of the end in the Y + direction in the drawing possible area of the drawing paper 26. Then, two cross patterns P + ₁ and P + ₂ separated in the X direction are drawn, and the processing for the first screen is completed.

Subsequently, as shown in FIG. 1C, the operator feeds the drawing paper 26 in the -Y direction, and two cross patterns P + ₁ and P + _2, which are reference points for screen connection, are placed on the drawing board 2. When the drawing resuming command is input in the vicinity of the Y-direction reference point of, the CPU 16 moves the head carriage 6 to the vicinity of the origins X ₀ and Y ₀ of the drawing area as shown in FIG. 1D. Search the cross pattern P + ₁ from the image of 8.

Then, similarly to the writing tool error correction described above, the pattern matching function is used to detect the pattern and perform XY.
After the coordinates are calculated, as shown in FIG. 2A, the head carriage 6 is moved to the vicinity of X _max and Y ₀ of the drawing area to search the image of the video camera 8 for the cross pattern P + ₂ and Detection and XY coordinate calculation are performed.

The CPU 16 uses the XY coordinates of the detected two cross patterns P + ₁ and P + ₂ as a reference, and the CPU 16 of FIG.
As shown in, the coordinate system of the drawing data on the second screen is corrected and the drawing is executed. Therefore, regardless of the displacement of the reference coordinates due to the movement of the paper 26, a drawing result in which the first screen and the second screen are continuous as shown in FIG. 2C can be obtained.

Further, when the coordinate correction is performed on the graph paper 27 set on the drawing board 2 as shown in FIG. 5, if an execution command of the reference coordinate three-point correction is input, as shown in FIG. The head carriage 6 moves to the vicinity of the origin of the drawing board 2,
The origin P0 of the graph paper 27 is searched through the video camera 8 to obtain the coordinate data of the origin P0. Hereinafter, the head carriage 6 is sequentially moved to the vicinity of X _max , Y _{0 and the} vicinity of X ₀ , Y _{max of} the drawing area, and the ruled line intersection P1 on the X reference line,
Since the coordinate data of the ruled line intersection P2 on the Y reference line is acquired and the coordinate system of the drawing data is corrected based on the acquired coordinate data of the three points, the grid line of the graph paper 27 and the reference coordinates of the drawing result match. To do.

Further, the present invention is not limited to the above-mentioned embodiment. For example, instead of the pattern matching method, each process of contour extraction, skeleton extraction and intersection extraction is performed on the image data, and the intersection coordinates of a cross pattern or the like are obtained. It is natural that the present invention extends to the modified ones such that the present invention extends to such modified ones.

[0025]

As described above in detail, according to the present invention, when the image is drawn on the graph paper, the coordinate correction work for matching the ruled line of the graph paper and the drawing coordinates and the connecting portion of the long drawing which is divided and drawn. Since the coordinate correction work to match the is automatically performed by using the video image processing, the user does not need to manually input the correction value using the loupe,
Workability is significantly improved. Further, there is no deviation of the correction value due to individual differences, and the invention contributes to improvement of drawing quality.

[Brief description of drawings]

FIG. 1 shows an XY plotter of the present invention, (a) and (b).
(C) and (d) are explanatory diagrams showing the connection coordinate correction operation.

2 (a), (b) and (c) are explanatory views showing a connection coordinate correction operation subsequent to FIG.

FIG. 3 is a circuit block diagram of an XY plotter of the present invention.

4 (a), (b), (c) and (d) are explanatory diagrams showing a procedure of detecting a coordinate displacement amount by the image analysis device.

5 (a), (b), (c), and (d) are explanatory views of a three-point coordinate correction operation for graph paper.

[Explanation of symbols]

 1 XY Plotter 6 Head Carriage 8 Video Camera 9 Plotter Control Unit 10 Video Signal Input Device 12 Frame Memory 16 CPU 17 ROM 18 Data Memory 25 Image Analysis Device 26 Drawing Paper 27 Graph Paper

Claims (2)

[Claims] 1. A video camera for photographing a drawing board surface is mounted on a writing instrument driving head carriage of an XY plotter, a control means for forming a cross pattern on a screen, and the cross pattern from photographed image data of the video camera. An XY plotter provided with an image analysis device for detecting the center point of the cross pattern, and an arithmetic unit for obtaining coordinate correction data from the amount of displacement between the center coordinates of the cross pattern and the reference coordinates of the imaging screen to correct the coordinate system of the drawing data. In the case of dividing the drawing data of a size exceeding the drawing area into a plurality of pages and drawing the image, a control means for forming a cross pattern at two points near the last line of each page, and the head at the time of starting the drawing of the next page. Control means for moving the carriage near the start line of the drawing area to automatically search for the cross pattern by the video camera, and the detected cross pattern of the two points. A coordinate correction device for an XY plotter, which is provided with a calculation means for correcting the coordinate system of the drawing data on the next page based on the center coordinates. 2. A writing means driving head carriage of an XY plotter is equipped with a video camera for photographing a drawing board surface, control means for forming a cross pattern on a screen, and the cross pattern from the image data taken by the video camera. An XY plotter provided with an image analysis device for detecting the center point of the cross pattern, and an arithmetic unit for obtaining coordinate correction data from the amount of displacement between the center coordinates of the cross pattern and the reference coordinates of the imaging screen to correct the coordinate system of the drawing data. At this point, the head carriage is driven in response to a command, and the video camera and the image analysis device make three points of the origin of the grid pattern on the drawing board on the XY axis, the ruled line intersection on the X axis, and the ruled line intersection on the Y axis. In the XY plotter, there are provided control means for automatically searching for and a control means for correcting the coordinate system of the drawing data based on the detected coordinates of the three points. Coordinate correction device.