Image measuring instrument and program

Abstract

The invention provides an image measuring instrument and a computer program product. The image measuring instrument can reduce work required in image measurement in the prior art. An image measuring instrument is provided with: a CAD data storage unit that stores CAD data and CAD data information for at least one article in advance for each different CAD data; a CAD data retrieval unit that retrieves, from the CAD data storage unit, CAD data in which the shape of the article is similar to the shape of the object to be measured represented by the captured image; a CAD data setting unit that optimally fits the CAD data identified on the basis of the search as the CAD data to be measured to the image to be measured, and sets a coordinate system of the optimally fitted CAD data as a measurement coordinate system; and a measurement execution unit that executes edge detection and size measurement for each measurement site on the image of the measurement target using CAD data information corresponding to the CAD data of the measurement target.

Description

Technical Field

[0001] The present invention relates to an image measuring instrument and a program. Background Art

[0002] A vision measuring instrument (image measuring machine) is a device that captures an image of a measurement object and measures the dimensions of a measurement portion of the measurement object by analyzing the image (for example, see Patent Document 1).

[0003] Prior art literature

[0004] Patent Literature

[0005] Patent Document 1: (Japanese) Patent Publication No. 2010-169584 Summary of the invention

[0006] Problems to be solved by the invention

[0007] In the past, when measuring images, it was necessary to prepare a partial program that recorded the measurement content and steps for each measurement object, set the measurement coordinate system according to the position and orientation of the measurement object on the mounting table, and manually set the edge detection tool for determining the range of edge detection processing for each measurement location.

[0008] An object of the present invention is to provide a vision measuring instrument and a program capable of reducing the work conventionally required when measuring an image.

[0009] Means for solving problems

[0010] The image measuring instrument of the present invention is an image measuring instrument that captures an image of a measurement object and measures the dimensions of a measurement portion of the measurement object by analyzing the image, and comprises: a CAD data storage unit that stores CAD data and CAD data information of at least one object in advance for each different CAD data, the CAD data information including a design dimension extracted from the CAD data, a measurement portion corresponding to the design dimension, and a condition of an edge detection tool used for edge detection of the measurement portion; a CAD data retrieval unit that retrieves CAD data of a measurement object having a shape similar to that represented by the captured image from the CAD data storage unit; a CAD data setting unit that best fits the CAD data determined based on the retrieval as the CAD data of the measurement object to the image of the measurement object and sets the coordinate system of the best-fitting CAD data as the measurement coordinate system; and a measurement execution unit that performs edge detection and dimension measurement for each measurement portion on the image of the measurement object using the CAD data information corresponding to the CAD data of the measurement object.

[0011] It may further include: a display unit; a CAD data setting unit causing the display unit to overlap the best-fit CAD data of the measurement object on the image of the measurement object and display it; and a measurement execution unit causing the measurement result to be displayed at the display position of the design dimension of each measurement part in the CAD data of the measurement object.

[0012] The CAD data information may include information on the tolerance of the design dimension, and when the measurement result of each measurement location is outside the tolerance range of the design dimension, the measurement execution unit may display the measurement result on the display unit in a manner that allows identification of the outside of the range.

[0013] The functions of the vision measuring instrument of the present invention may be written as a program, and the functions of the vision measuring instrument of the present invention may be realized by causing a computer to execute the program.

[0014] Effects of the Invention

[0015] According to the vision measuring instrument and program of the present invention, it is possible to omit operations such as generation of a part of the program, setting of the measurement coordinate system, setting of the edge detection tool, etc., which are conventionally required for image measurement, and thus it is possible to reduce the operations of image measurement. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 FIG. 1 is a diagram showing an example of the appearance of a vision measuring machine 1 that executes the image measuring method of the present invention.

[0017] Figure 2 1 is a schematic diagram showing the internal structure of the vision measuring machine 1 .

[0018] Figure 3 1 is a functional block diagram of the vision measuring machine 1 .

[0019] Figure 4 This is a diagram showing an example of CAD data of an article.

[0020] Figure 5 FIG. 1 is a diagram showing an example of a captured image of a measurement object.

[0021] Figure 6 This is a diagram showing an example of optimally fitting CAD data to a captured image.

[0022] Figure 7 This is a diagram showing an example of how measurement results are displayed.

[0023] Figure 8 FIG. 1 is a diagram showing an image for operating the display of measurement results. DETAILED DESCRIPTION

[0024] Below, while referring to the attached Figure 1In the following description and drawings, the same reference numerals are given to the same functional parts, and the description of the functional parts that have been described once is omitted or described only within the necessary scope.

[0025] Figure 1 1 is a schematic diagram showing an example of the appearance of the vision measuring device 1 of the present invention. Figure 2 1 is a schematic diagram showing an example of the internal structure of the vision measuring machine 1 . Figure 3 1 is a functional block diagram of the vision measuring machine 1. In the present embodiment, a case where the coaxial incident illumination method is used as the illumination method is described as an example, but the illumination method is not relevant as long as an image of the measurement object can be captured.

[0026] The vision measuring machine 1 includes a mounting table 2 , an imaging unit 3 , a control and calculation unit 4 , a storage unit 5 , a display unit 6 , a telecentric optical system 7 , an illumination unit 8 , and an operation unit 10 .

[0027] The mounting table 2 is a platform on which a measurement object (not shown) is mounted.

[0028] The imaging unit 3 is arranged opposite to the mounting table 2, and captures an image by receiving light from the direction of the mounting table 2. The imaging unit 3 includes an image sensor, and converts the brightness of the image formed on its light receiving surface into an electrical signal as image data. The image sensor adopts a CCD (Charge-Coupled Device) charge-coupled device or a CMOS (Complementary Metal Oxide Semiconductor) complementary metal oxide semiconductor, and the charge-coupled device is a semiconductor solid-state imaging element.

[0029] The display unit 6 is an arbitrary display means, and displays an image captured by the imaging unit 3 and the like.

[0030] The telecentric optical system 7 includes an objective lens 71 for collecting light from the direction of the mounting table 2 and an imaging lens 72 for forming an image of the light reaching through the objective lens 71 on a light receiving surface of the imaging unit 3. The objective lens 71 and the imaging lens 72 may be provided separately in the form of a multi-faceted lens.

[0031] The illumination unit 8 is a coaxial epi-illumination unit, which includes: a light source 81 that emits illumination light; and a beam splitter (BeamSplitter) 82, which adds the illumination light from the light source 81 to the telecentric optical system 7, and irradiates the illumination light as coaxial epi-illumination light whose optical axis is consistent with the optical axis of the imaging unit 3 toward the mounting table 2. The illumination unit 8 may also include transmitted illumination and side illumination together with the coaxial epi-illumination for the purpose of image clarity, etc.

[0032] The operation unit 10 is an input unit for inputting information required for measurement. Figure 1 , 2 In the embodiment, an example is shown in which a touch panel display is used and integrated with the display unit 6, but the present invention is not limited to this and may be configured as an independent input unit.

[0033] The storage unit 5 is any storage means capable of storing digital data. In the present invention, the storage unit 5 includes a CAD data storage unit 51 .

[0034] The CAD data storage unit 51 stores the CAD data of the article and the CAD data information in advance for each different CAD data. The CAD data information includes the design dimensions extracted from the CAD data, the measurement parts corresponding to the design dimensions, and the conditions of the edge detection tool used for edge detection of the measurement parts. If necessary, the tolerance can also be stored together with the design dimensions.

[0035] Figure 4 An example of CAD data representing an object. In CAD data, information such as the outline, hidden lines, and center lines representing the shape of the object is also included in the design dimensions, dimensional tolerances, dimension lines, dimension auxiliary lines, and lead lines. Therefore, for example, by using the record of the design dimensions as a clue and tracing according to the order of the dimension lines corresponding to the design dimensions and the dimension auxiliary lines corresponding to the dimension lines, the location and shape of the outline corresponding to the design dimensions can be determined, and further, the conditions of the edge detection tool applicable to the location can also be determined. In addition, when designing with CAD, it is usually specified which graphic element is used to illustrate the dimensions (length, diameter, radius, etc.), so the CAD data can include link information between the dimension value and the graphic element. Therefore, this associated information can also be used to achieve efficient processing of determining the location and shape of the outline.

[0036] CAD data information can be generated by such processing. However, application software that outputs CAD data information may be prepared to improve the efficiency of the generation process. The application software automatically performs the generation process based on the input of CAD data.

[0037] The control and calculation unit 4 controls each unit in the vision measuring machine 1 and performs necessary calculation processing in order to realize image capturing and image measurement by the vision measuring machine 1 .

[0038] The control operation unit 4 in the present invention includes a CAD data search unit 41 , a CAD data setting unit 42 , and a measurement execution unit 43 .

[0039] The CAD data search unit 41 searches the CAD data storage unit 51 for CAD data having a shape similar to the measurement object represented on the image captured by the image capturing unit 3. Any method can be used to determine the similarity. For similar CAD data, the data with the highest similarity can be determined, or a plurality of high-order data can be temporarily determined. In the case where a plurality of high-order data are temporarily determined, for example, the display unit 6 can be made to display the plurality of high-order data, and one of them can be determined by receiving input of information for determining one of them.

[0040] The CAD data setting unit 42 uses the CAD data determined based on the search by the CAD data search unit 41 as the CAD data of the measurement object, makes it best fit to the image of the measurement object, and sets the coordinate system of the best fitted CAD data as the measurement coordinate system. The method of making the CAD data best fit to the image of the measurement object can also adopt any method such as pattern matching or parameter matching.

[0041] For example, when the search determines Figure 4 The CAD data shown is similar to the Figure 5 When the CAD data of the measurement object represented by the captured image shown in the figure is Figure 6 As shown, Figure 4 The CAD data shown is a best fit to Figure 5 By best fitting, the position range of the measurement object in the coordinate system of the CAD data can be associated with the position range of the measurement object in the measurement coordinate system grasped from the captured image, so that the coordinate system of the CAD data can be set as the measurement coordinate system.

[0042] The measurement execution unit 43 performs edge detection and dimension measurement for each measurement site on the image of the measurement target using CAD data information corresponding to the CAD data of the measurement target stored in the CAD data storage unit 51 .

[0043] In addition, it is also possible to configure that, for each CAD data, before the first measurement is performed, the lighting conditions of the lighting unit 8 can be automatically or manually set so that the contrast of the measurement part becomes the maximum. It is also possible to further configure that the lighting conditions set for each measurement part are stored in the CAD data storage unit 51 in the form of addition to the CAD data information, and the lighting conditions are automatically set when the second and subsequent measurements are performed.

[0044] The CAD data setting unit 42 may cause the display unit 6 to superimpose the best-fitted CAD data of the measurement object on the image of the measurement object for display, and the measurement execution unit 43 may display the measurement result at the display position of the design dimensions of each measurement part in the CAD data of the measurement object. Figure 7This shows an example of how measurement results are displayed. Figure 7 , an example is shown in which the measurement result is displayed superimposed on the design dimension display in the CAD data, but it is also possible to display them without overlapping but slightly offset, or to display the design dimension display instead of the measurement result.

[0045] The information of the tolerance of the design dimension of the measurement part may be added to the CAD data information stored in the CAD data storage unit 51. When the measurement result of each measurement part is outside the tolerance range of the design dimension, the display unit 6 may display it in a manner that can identify that it is outside the range. The identification method may be arbitrary, for example, the color or font of the display of the measurement result may be changed, or a sentence indicating that it is outside the range may be displayed at an arbitrary position.

[0046] The present invention can be constituted by a CPU to control the operation unit 4, and by executing the program recording the following functions with the CPU, each function can be realized: the functions of the CAD data retrieval unit 41, the CAD data setting unit 42, and the measurement execution unit 43, the function of controlling the shooting unit 3, the lighting unit 8, etc. The program can also read out the program stored in the storage unit 5, and can also read out the content stored in another storage unit. In addition, the control operation unit 4 and the storage unit 5 can be provided in the image measuring instrument 1 itself, or can be provided by a device such as a personal computer that can be connected to the main body of the image measuring instrument 1 in a communication manner.

[0047] According to the vision measuring instrument and program of the present invention described above, it is possible to omit the work of writing part of the program, setting the measurement coordinate system, setting the edge detection tool, adjusting the display position of the measurement result, etc., which are conventionally required in image measurement, and to reduce the work of image measurement.

[0048] Furthermore, since the CAD data is fitted to the image of the measured object, Figure 8 As shown, the display of the measurement result can be enlarged, reduced, rotated or scrolled on the screen. In addition, when fitting the CAD data based on the CAD data setting unit 42, the information of the position and posture of the measurement object can be obtained, so the measurement result can be automatically enlarged, reduced, rotated, moved using this information, and displayed in a way that is easy for the user to read.

[0049] The present invention is not limited to the above-mentioned embodiments and variations. The above-mentioned embodiments and variations are examples, and they have substantially the same structure as the technical ideas recorded in the claims of the present invention, and any one of them that exerts the same effect is included in the technical scope of the present invention. That is, appropriate changes can be made within the scope of the technical ideas represented in the present invention, and the method to which such changes or improvements are applied is also included in the technical scope of the present invention.

[0050] Description of Reference Numerals

[0051] 1 Image measuring instrument

[0052] 2 Loading table

[0053] 3. Filming Department

[0054] 4 Control calculation unit

[0055] 5 Storage

[0056] 6 Display

[0057] 7 Telecentric optical system

[0058] 8 Lighting Department

[0059] 10 Operation section

[0060] 41 CAD Data Retrieval Department

[0061] 42 CAD data setting department

[0062] 43 Measurement execution unit

[0063] 51 CAD data storage unit

Claims

1. An image measuring instrument that captures an image of a measurement object and measures the size of a measurement portion of the measurement object by analyzing the image, comprising: A CAD data storage unit that stores CAD data of at least one object and CAD data information for each different CAD data in advance, wherein the CAD data information includes a design size extracted from the CAD data, a measurement part corresponding to the design size, and a condition of an edge detection tool for edge detection of the measurement part; a CAD data retrieval unit that retrieves CAD data of the measurement object having a shape similar to that represented by the captured image from the CAD data storage unit; a CAD data setting unit that best fits the CAD data determined based on the search as the CAD data of the measurement object to the image of the measurement object, and sets a coordinate system of the best-fitting CAD data as a measurement coordinate system; as well as The measurement execution unit detects edges and measures dimensions for each measurement portion using the CAD data information corresponding to the CAD data of the measurement object on the image of the measurement object.

2. The image measuring instrument according to claim 1, characterized in that: The device further comprises: a display unit, The CAD data setting unit causes the display unit to display the best-fit CAD data of the measurement object by superimposing it on the image of the measurement object. The measurement execution unit displays the measurement result at a display position of a design dimension of each measurement part in the CAD data of the measurement object.

3. The image measuring instrument according to claim 2, characterized in that: The CAD data information includes information on the tolerance of the design dimensions. When the measurement result of each measurement location is outside the tolerance range of the design dimension, the measurement execution unit causes the display unit to display the measurement result in a manner that allows recognition that the measurement result is outside the tolerance range.

4. A computer program product, characterized in that The computer program product comprises a computer program, When the computer program is executed by a computer, the computer is caused to function as the vision measuring instrument according to any one of claims 1 to 3.

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