JPH09250909A - Method and system for measuring image without contact - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve operativity at measurement by generating a new tool along the edge contained in an imaged sample image. SOLUTION: By specifying multiple points 43 an the edge contained in an imaged image of a work 12, an approximate curve 44 joining them is generated, and a tool 45 of an arbitrary form containing the approximate curve 44 inside it is generated along the approximate curve 44. Thus, even when the form of work 12 is a complex one other than a straight line or a circle, no troublesome operation is required, so operativity is improved.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention carries out image measurement such as shape measurement while detecting an edge on a tool by superimposing and displaying an edge detection tool on an image of an object to be measured picked up by an image pickup means. The present invention relates to a non-contact image measuring method and system, and more particularly to a non-contact image measuring method and system most suitable for shape measurement of an object to be measured having a complicated shape.

[0002]

2. Description of the Related Art Conventionally, in this type of non-contact image measuring system, when a shape of a work to be measured is measured, the measurement range is shown by being superimposed on a work image picked up by an image pickup means such as a CCD camera. Edge detection tool (hereinafter,
It is called a tool. ) Is displayed, and the edge included in the work image is detected on this tool. FIG. 10 is a diagram showing an example of a tool used for such edge detection. The tools 61 to 64 are set at arbitrary positions on the screen of the CRT display, which is a display means, via an input device such as a mouse provided in the non-contact image measurement system, and the measurement range set accordingly. Edges are detected along the direction of the arrow in the figure while updating the sampling positions at regular intervals in the direction orthogonal to the direction of the arrow in the figure. Therefore, the tools 61 to 64 are selected according to the shape of the workpiece 12 to be measured or the measurement purpose such as point measurement, line measurement, or circle measurement.

[0003]

By the way, with the recent diversification of workpieces, there is an increasing number of cases where a smooth curved line shape other than a straight line or a circle or a more complicated shape is measured. However, in the above-described conventional non-contact image measurement system, for example, when the measurement is performed on the work 12 having the shape as shown in FIG.
As shown in (a), when only one tool 63 is selected and the measurement range is set, a plurality of edge points 65 are included at each sampling position, or the measurement range becomes large, and it takes time to perform image processing. It will take. Therefore, FIG.
As shown in (b) and FIG. 12 (c), a plurality of tools 61, 63 are set along the edge to be measured of the work 12, but since a plurality of different types of tools are set, There is a problem that it takes time to operate.

The present invention has been made in order to solve such a problem, and when a new tool is generated along an edge included in an image of an object to be measured, a new tool is used. An object of the present invention is to provide a non-contact image measuring method and system capable of improving operability.

[0005]

A non-contact image measuring system according to the present invention comprises an image pickup means for picking up an image of an object to be measured, and a display means for displaying the image of the object to be measured picked up by the image pickup means. The display means displays a tool indicating a measurement range overlaid on the image of the object to be measured, and a control means for detecting an edge from image information on the tool to extract information necessary for measurement. The means generates an approximated curve connecting a plurality of points specified on an edge included in the image to be measured, and generates an arbitrary shape tool including the approximated curve inside along the approximated curve. Is characterized in that.

Another non-contact image measuring system according to the present invention further comprises storage means for storing the tool generated by the control means as a custom tool, and the control means comprises:
When measuring a measured object of the same type as the measured object that generated the tool, the tool stored in the storage means is read out and displayed on the display means by being superimposed on the image of the measured object. Is characterized in that.

The non-contact image measuring method according to the present invention comprises the steps of designating a plurality of points on the edge of the image to be measured, and the step of generating an approximate curve connecting the plurality of points designated in this step. , A step of generating a tool for edge detection so as to include the approximate curve therein along the approximate curve generated in this step, and extending in a direction orthogonal to the approximate curve in the tool generated in this step The method is characterized by comprising the steps of sampling the intersections of a plurality of straight lines and the edges of the image to be measured, and extracting the information necessary for measurement based on the intersections sampled in this step.

According to the non-contact image measuring system of the present invention, an approximate curve connecting a plurality of points designated on an edge included in the image of the object to be measured picked up by the image pickup means is generated and the approximate curve is generated. A tool of arbitrary shape including an approximate curve inside is generated along with, so even if the shape of the measured object is a smooth curve other than a straight line or a circle, or if it is more complicated, the tool setting operation is troublesome. Therefore, the operability can be improved.

If a new tool generated by the control means is registered in the storage means as a custom tool, the new tool registered in this storage means can be used any number of times in the subsequent measurement. Therefore, it is possible to further simplify the operation when repeatedly measuring the same type of object to be measured. In addition, by registering multiple custom tools of such arbitrary shapes for each shape of the object to be measured, it is possible to call up and use the registered tools according to the object to be measured, enabling a significant reduction in man-hours. Become.

[0010]

Embodiments of the present invention will be described below with reference to the accompanying drawings. FIG. 1 is a perspective view showing the overall configuration of a non-contact image measuring system according to an embodiment of the present invention. This system is a non-contact image measuring type three-dimensional measuring machine 1, and drives and controls the three-dimensional measuring machine 1.
Computer system 2 for performing necessary data processing
And a printer 3 that prints out the measurement result.

The coordinate measuring machine 1 is constructed as follows. That is, a measurement table 13 on which a work 12 is placed is mounted on the gantry 11.
3 is driven in the Y-axis direction by a Y-axis drive mechanism (not shown). Support arms 14 and 15 extending upward are fixed to the center of both side edges of the gantry 11.
An X-axis guide 16 is fixed so as to connect both upper ends of the X-ray guides 4 and 15. An imaging unit 17 is supported by the X-axis guide 16. The image pickup unit 17 is driven along the X-axis guide 16 by an X-axis drive mechanism (not shown). At the lower end of the imaging unit 17, a CCD camera 18 is mounted so as to face the measurement table 13. In addition, inside the image pickup unit 17, a CCD camera 18 is provided in addition to an illumination device and a focusing mechanism not shown.
The built-in Z-axis drive mechanism moves the position in the Z-axis direction.

The computer system 2 comprises a computer main body 21, a keyboard 22, a joystick box 23, a mouse 24 and a CRT display 25. The computer body 21 is, for example, as shown in FIG.
It is configured as shown in FIG. That is, the CCD camera 18
The image information input from the
/ F) 31 and is stored in the multi-valued image memory 32. The multi-valued image information stored in the multi-valued image memory 32 is displayed on the CRT display 25 via the display control unit 33. On the other hand, the position information input from the mouse 24 is input to the CPU 35 via the I / F 34. CP
U35 generates an approximate curve connecting points specified by the mouse 24 according to a program stored in the program memory 36, generates a new tool along the calculated approximate curve, saves the generated tool, and The multi-valued image information on this tool is extracted from the multi-valued image memory 32, and the processing for detecting edge points is sequentially executed. Work memory 37
Provides a work area for various processes in the CPU 35. The storage device 38 stores the generated tool as a custom tool, and is composed of a hard disk device or the like.

Next, a tool generating procedure in the non-contact image measuring system configured as above will be described.
FIG. 3 is a flowchart showing a tool generation process of the system, and FIGS. 4 and 5 are CRTs for explaining this process.
Image information 4 of the work 12 displayed on the display 25
FIG.

First, as shown in FIG.
The cursor 42 of 4 is moved, and a plurality of arbitrary points 43 on the edge of the workpiece 12 to be measured are designated by a click operation at appropriate intervals. Hereinafter, these designated points 43 will be referred to as connection points 43 (S1). As shown in FIG. 4B, when a plurality of connecting points 43 are designated, the CPU 35
Interpolates between the designated connecting points 43 with an approximate curve such as a Bezier curve to generate an approximate curve 44 along the edge of the work 12 (S2). Below, CRT display 2
These processes are repeated (S1 and S2) until the end button (not shown) displayed on the screen 5 is pressed by the operation of the mouse 24 (S3).

When the end button is pressed (S3), the CPU
35 is shown along the approximate curve 44 shown in FIG.
The tool 45 shown in (b) is generated (S4). That is, C
As shown in FIG. 6A, the PU 35 first sets a plurality of straight line vectors 49 that are orthogonal to the approximate curve 44 and have the same distance between the intersection point 46 and the start point 47 and the intersection point 46 and the end point 48 along the approximate curve 44. Generate at regular intervals. The generated straight line vector 49 becomes a detection tool at the time of edge detection. Next, as shown in FIG. 6B, the CPU 35 connects the start points 47 and the end points 48 of the obtained straight line vector 49 with an approximate curve 50 such as a Bezier curve. This allows
A tool 45 as shown in FIG. 5B is generated. When the tool 45 is generated, the CPU 35 registers the obtained straight line vector 49 and the two curves 50 as tool information in the storage device 38 (S5).

As described above, according to the present embodiment, a custom operation according to the shape of the workpiece 12 can be performed by a simple operation of designating a plurality of connecting points 43 on the edge included in the imaged image of the workpiece 12. Since the tool 45 can be generated, even if the shape of the work 12 is complicated other than a straight line or a circle, the tool setting operation does not take time and the operability can be improved. Further, according to the present embodiment, by registering the generated tool 45, it is possible to display the registered tool 45 again on the image of the work 12 and repeatedly measure the same type of work 12. The operation can be simplified in the shape measurement to be performed.

By the way, the tool 45 generated along the edge of the work 12 is a single planar tool, and the operability can be further improved by providing a correction function for the registered tool 45. it can. FIG. 7 is a flowchart showing a tool extension process in the system, FIG.
FIG. 4 is a diagram showing image information 41 showing a part of the work 12 displayed on the CRT display 25 for explaining this processing.

First, as shown in FIG. 8A, the connecting point 43 is designated by clicking with the mouse 24 the position where the edge of the workpiece 12 to be additionally measured and the outer peripheral portion of the tool 45 intersect. S11). Next, when a plurality of connecting points 43 are specified, the CPU 35 performs the above-described approximate curve interpolation processing, and the approximate curve 44 along the edge of the work 12.
Is generated (S12). Below, CRT display 25
The end button (not shown) displayed on the screen of the mouse 2
These processes are repeated (S11 to S12) until pressed by the operation of 4 (S13). When the end button is pressed (S13), the CPU 35 generates a tool 45 'extended along the approximate curve 44, as shown in FIG. 8 (b) (S14).

In this embodiment, it is possible to identify that the tool expansion process is performed by designating the position where the edge of the work 12 and the outer peripheral portion of the tool 45 intersect. It is also possible to divide the registered tools 45 by specifying a plurality of them. That is, as shown in FIG. 9A, a plurality of division points 51 are designated by clicking a predetermined position on the outer circumference of the tool 45 to be changed with the mouse 24, and as shown in FIG. By connecting these division points 51 to generate a straight line vector 52, selecting the tool 45a and deleting the tool 45b, the tool 45a shown in FIG. 9C can be obtained.

[0020]

As described above, according to the present invention, an approximation curve connecting a plurality of points designated on an edge included in the image of the object to be measured imaged by the imaging means is generated and the approximation curve is generated. Since a tool with an arbitrary shape that contains an approximate curve along the curve is generated, even if the shape of the measured object is complicated other than a straight line or a circle, it does not take time to set the tool and the operability is improved. Can be made.

[Brief description of drawings]

FIG. 1 is a perspective view showing a configuration of a non-contact image measuring system according to an embodiment of the present invention.

FIG. 2 is a block diagram of a computer main body in the same system.

FIG. 3 is a flowchart of a tool generation process in the system.

FIG. 4 is a diagram for explaining a tool generation process in the system.

FIG. 5 is a diagram for explaining a tool generation process in the system.

FIG. 6 is a diagram for explaining a tool generation process in the system.

FIG. 7 is a flowchart of a tool extension process in the system.

FIG. 8 is a diagram for explaining a tool extension process in the system.

FIG. 9 is a diagram for explaining a tool dividing process in the system.

FIG. 10 is a diagram showing an example of a tool in a conventional example.

FIG. 11 is a diagram showing an example of a work image.

FIG. 12 is a diagram for explaining a tool creation method in a conventional example.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Coordinate measuring machine, 2 ... Computer system, 3 ... Printer, 11 ... Stand, 12 ... Work, 13 ... Measurement table, 14, 15 ... Support arm, 16 ... X-axis guide, 17
... Imaging unit, 18 ... CCD camera, 21 ... Computer body, 22 ... Keyboard, 23 ... Joystick box, 24 ... Mouse, 25 ... CRT display,
31, 34 ... Interface, 32 ... Multi-valued image memory,
33 ... Display control unit, 35 ... CPU, 36 ... Program memory, 37 ... Work memory, 41 ... Image information, 42 ... Cursor, 43 ... Connection point, 44, 50 ... Approximate curve, 45,
45 ', 45a, 45b, 61-64 ... Tool, 46 ...
Intersection points, 47 ... Start point, 48 ... End point, 49, 52 ... Straight line vector, 51 ... Dividing point, 65 ... Edge point.

Claims (3)

[Claims] 1. An image pickup means for picking up an image of the object to be measured, a display means for displaying the image of the object to be measured picked up by the image pickup means, and a measurement range superimposed on the image of the object to be measured on the display means. And a control means for displaying an edge from the image information on the tool and extracting the information required for measurement, and the control means is on the edge included in the image of the measurement target. A non-contact image measurement system, which generates an approximate curve connecting a plurality of designated points and generates a tool having an arbitrary shape including the approximate curve therein along the approximate curve. 2. A storage unit for storing the tool generated by the control unit as a custom tool, wherein the control unit stores a measurement target of the same type as a measurement target of the generation of the tool. The non-contact image measurement system according to claim 1, wherein the tool stored in the storage means is read out and displayed on the display means so as to be superimposed on the image of the object to be measured upon measurement. 3. A step of designating a plurality of points on an edge of an image to be measured, a step of generating an approximation curve connecting the plurality of points designated in this step, and an approximation curve generated in this step. Along with the step of generating a tool for edge detection so as to include the approximate curve therein, a plurality of straight lines extending in a direction orthogonal to the approximate curve in the tool generated in this step, and the measured object A non-contact image measuring method comprising: a step of sampling an intersection with an edge of an image; and a step of extracting information necessary for measurement based on the intersection sampled in this step.