JP2002228424A - Offline teaching method for image measuring device by optimization of illuminating condition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method capable of offline teaching by setting optimum illuminating conditions for image measurement and of improving reliability in automatic measurement by simulating illumination under the conditions and previously verifying the set conditions. SOLUTION: This offline teaching method for the image measuring device by the optimization of the illuminating conditions is comprised of both a first step for individually setting illuminance reference values of a plurality of illuminating devices provided for the image measuring device and directed toward an object to be measured from the actual color of the object to be measured and material data and a second step for correlating the illuminance of each illuminating device to the characteristic geometric shape of a part to be measured and setting the illuminance as a ratio to the reference value set in the first step on the basis of three-dimensional CAD data on the object to be measured.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of non-contact measurement of an object to be measured by an image measuring device, and more particularly to a method of off-line teaching in which optimal illumination conditions are set efficiently.

[0002]

2. Description of the Related Art In recent years, with the progress of miniaturization, weight reduction and high density of precision machines and electronic parts, measurement of minute parts where a stylus of a measuring instrument cannot enter a measurement object has increased. ,
Inspection items are increasing. In addition, when a force is applied to a measured object with a stylus at the time of measurement, the thickness of the measured object tends to be so thin that the measured portion is easily deformed. For this reason, there is an increasing demand for dimensional measurement performed by an operator without any contact with a measurement object, such as observation with a microscope or a projector.

[0003] However, it has been difficult to reduce the inspection time and the number of work steps because the measurement operator has been performing the check inspection by visual observation. Inevitable measurement errors were inevitable. In order to solve such a problem, a technique of mechanically measuring a measured object in a non-contact state by using an image measurement three-dimensional measuring machine that has been rapidly spread recently has been developed. Among them, there are products and research reports on image measurement using computer and CAD technology.

When such a three-dimensional measuring machine for image measurement is used, it is easy for a machine to measure an individual measurement object (eg, a geometrical shape such as an edge, a hole, a hole, a plane, or a step surface). The lighting conditions for imparting contrast must be set so that the characteristics of each part as a simple three-dimensional element are expressed on the monitor screen, and that part can be recognized and measured by a computer. .

Until now, the lighting conditions of these three-dimensional measuring machines cannot be set automatically, so that the operator can easily see the illuminance of the illuminating device manually based on the manual when measuring. After that, the measurement device is controlled and the measurement is performed by eye.

In order to automatically measure an object to be measured, an off-line teaching of an image measuring machine must be performed in advance and suitable lighting conditions must be set. The setting of the illumination conditions can be performed manually for the image measuring device based on a setting manual for each of the measured objects individually. In this setting, the actual condition is visualized by a computer on a monitor, and the condition of the optimum state is determined by taking time and effort while viewing the image. As described above, it has been very difficult to set appropriate measurement conditions required for off-line measurement. Until now, there has been no means for verifying whether the lighting conditions thus set are optimal.

[0007]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned circumstances, and in particular, utilizes the CAD technology of a computer in the field of high-mix low-volume production and the prototype development process where automation is considered difficult. In order to adapt the 3D measuring machine flexibly and perform highly reliable measurement smoothly, the measurement procedure and measurement conditions for various measurement objects are automatically generated and the image measurement is performed. The present invention provides a method for easily or automatically setting an optimal lighting condition for a subject, and enabling efficient teaching even for a complicated and large number of inspection items.

[0008] Further, using the rendering function of the CAD system, an image at the time of measurement is simulated by a computer, and the optimality of the measurement conditions such as lighting once set by the above method is verified in advance, and the setting is performed. An object of the present invention is to provide a method in which when the lighting condition is not optimal, the lighting condition can be corrected and set again to the optimal lighting condition.

[0009]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention relates to a method of measuring a plurality of illuminations provided on an image measuring machine from an actual color and material data of a measured object toward the measured object. A first step of setting a standard value of the illuminance of the device;
Setting the illuminance of each of the lighting devices as a ratio to the standard value set in the first step, in accordance with the characteristic geometric shape of the part to be measured, based on the three-dimensional CAD data of the measurement object; And an off-line teaching method of the image measuring device by optimizing the illumination conditions.

Further, in the above configuration, the method for responding to the characteristic geometric shape of the portion for measuring the illuminance of each lighting device in the second step is a measurement function specialized for the geometric characteristic and a specific shape. This is performed by an image measurement support system including an image processing tool having a boundary determination function of determining a boundary of the image.

Further, in the above method, the coordinates of the three-dimensional CAD data of the object to be measured are superimposed so that the actual object of the object to be measured is the same position as that measured by the image measuring device, and the same coordinate position as each lighting device is used. The third step of setting virtual light source coordinates, and shading is applied to each part of the measured object of the three-dimensional CAD data by the rendering function of the CAD system based on the light sources at the coordinates at the set illuminance of each lighting device. A fourth step of outputting and displaying the shaded image represented in the same manner,

The optimality of the set lighting conditions is selected by selecting a shadow image of a portion to be verified on a measurement screen of the image measurement support system and selecting a specific shape from image processing tools provided in the image measurement support system. A fifth step of superimposing and displaying the shadow image,

When the edge of the object to be measured is illuminated under the set conditions, the clarity of the contrast between light and dark and the accuracy of the position and size of the edge are visually checked with the shadow image. A sixth step of changing the setting of the lighting condition and the position and size of the image processing tool, redisplaying the shaded image under the corrected setting condition, visually checking the shaded image, and setting the optimal lighting condition; Is an off-line teaching method for an image measuring machine by optimizing the illumination conditions.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of an off-line teaching method for an image measuring device by optimizing illumination conditions according to the present invention will be described below based on the embodiment.

According to the present invention, a measurement object such as a small electronic component is directed to the measurement object by using respective data as converted values obtained from basic data stored in advance for the color of the actual surface and the material of the actual object. A first step of temporarily setting the illuminance of each of the plurality of illuminating devices arranged at different positions and irradiation angles and types of irradiation on the image measuring device as a standard value,

The 3 used in the design for the measured object
Based on the dimensional CAD data, the optimum illuminance of each of the lighting devices is determined in accordance with the characteristic geometric shape of the part to be measured (for example, a hole, a straight line, a step, a through hole, and the shape around the hole). Is set as a ratio (%) to the standard value provisionally set in the first step.

That is, in the first step, the optimum illuminance of each lighting device is determined by specifying the color and the material, and in the second step, by the characteristic three-dimensional shape, even if there is no actual object to be measured, as offline teaching. It can be automatically set in advance.

As a method of responding to the characteristic geometric shape of the portion for measuring the illuminance of each lighting device in the second step, a measurement function specialized for the characteristic portion and a specific shape This can be efficiently performed by an image measurement support system including an image processing tool dedicated to a specific shape having a boundary determination function for determining a boundary. As the image processing tool, for example, a circular tool corresponding to a hole or a cylindrical shape, an arc tool corresponding to an arc which is a part of the hole or the cylindrical shape, a box tool corresponding to a straight line, and the like are used.

Although the illumination conditions set in the second step may be considered to be optimal as a whole, an actual object has a complicated shape configuration and does not reach the illuminance overlap or a shadow. Parts may occur. This is done by simulating (verifying) the set lighting conditions, whereby the unsuitable portion is grasped, and further corrected to obtain more optimal conditions.

A method of verifying the optimality of the set lighting conditions and correcting the unsuitable portion to optimize the illumination conditions is such that the actual measurement object is positioned at the same position as that measured by the image measuring machine. A third step of superimposing the coordinates of the three-dimensional CAD data and setting virtual light source coordinates at the same coordinate position as each lighting device, and a CAD system based on each light source at the coordinates with the set illuminance of each lighting device. A fourth step of outputting and displaying on a monitor a shadow image expressed as if shadows were given to each part of the three-dimensional CAD data by the rendering function;

The optimality of the set lighting conditions is selected by selecting a shadow image of a portion to be verified on a measurement screen of the image measurement support system, and selecting a specific shape from image processing tools provided in the image measurement support system. A fifth step of displaying on the monitor superimposed on the shadow image,

When the edge of the object to be measured is illuminated under the set conditions, the clarity of the contrast between light and dark and the accuracy of the position and size of the edge are visually confirmed on the shaded image displayed on the monitor. If confirmed, change the setting of the lighting conditions and the position and size of the image processing tool, re-display the shaded image under the corrected setting conditions, visually check this, and set the optimal lighting condition. It becomes possible through the above steps of the sixth step.

[0023]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described more specifically, including the apparatus part of an image measuring machine used and the software part of various computer programs used.

In the present invention, there are various types of image measuring machines which can be used. For example, Mitutoyo Corporation (model SQV2
02PRO) can also be used. The computer is a Hewlett-Packer company (model KAYA
KXU6 / 400) personal computer and Soli
SolidWorks99 (S), an interface for developing applications for dWorks CAD system
oldWorks Trademarks) and Windows
It can be used in the operating environment of wsNT 4.0 (trade name of MicroSoft).

When performing automatic measurement with the image measuring machine,
In addition to the measurement position, a part program in which information such as the arrangement of tools indicating the range of the image processing target, image processing conditions, lighting conditions, and a method of comparing with calculated values can be used. Therefore, a part program for automatic measurement is automatically generated using three-dimensional CAD data.

In the image measurement, a method of irradiating an illumination that emphasizes an edge to be measured is important. In particular, in automatic measurement, whether or not an edge can be determined is determined. The illumination device of the measuring instrument used is controlled by combining two pieces of transmitted illumination from the lower surface of the table, vertical oblique illumination from the objective lens, and a ring-shaped concave mirror, which are used when measuring through holes. Inclined illumination adjustable from 30 ° to 80 ° is available. Each illumination can be adjusted from 0% (extinguished) to 100%. Further, the inclined illumination can adjust the illuminance in four directions, left, right, front and rear on the table surface.

Next, a detailed description will be given of a case in which the automatic measurement of a minute portion of the case (precision molded resin product) of the mobile phone shown in FIG. 1 is performed. Then, the measurement function of the straight edge and the arc edge and the measurement function of the step were verified. First, a data exchange experiment was performed in which a three-dimensional solid model was input from a different type of CAD to the developed system. The format of the data used is ParaSolid (Ver10)
It is.

Next, off-line teaching was performed using the model, a part program for automatic measurement was automatically generated, and the image measuring machine was controlled. The measurement object used in the experiment was inside the resin case of the mobile phone, and the color was black with a general tolerance of ± 0.1 mm. Fine projections and holes are densely arranged.

The teaching method is based on the CAD
The data is displayed in a graphic window, and is used for selecting a linear edge or an arc, a circular edge, or a plane to be measured one by one at the time of teaching of the measurement procedure. The calculated value is automatically calculated from the shape of the selected CAD element. The method of indicating the comparison with the calculated value and the tolerance is the same as described above. The distance intersection angle and the like can be measured by adding a new procedure for calling a measured element and obtaining it by calculation in an edit window of the measurement procedure.
The measurement procedure is created simply by repeating this operation.

No special knowledge is required for the above operations. This is because measurement conditions and the like are automatically determined from CAD data and initially set standard values. However, when the measurement conditions and the like are changed by editing the procedure, it is necessary to know the features of the image measuring device, and it is considered that specialized knowledge of image measurement is required.

First, the illumination conditions are determined based on the color and material of the measured object and the lens magnification, and the optimum luminous intensity of each illumination device is input as a standard value. Next, for each measurement element selected on the CAD, it is determined from the shape of the element and the surrounding shape, and conditions suitable as a ratio to a standard value of luminous intensity are automatically set.

FIG. 2 shows a dialog box for inputting a standard value of the luminous intensity of each lighting device, in which an optimum luminous intensity for a black resin molded product is set. This standard value can be reused as long as the color and material are the same even if the product shape is changed, so that it can be made into a library.

FIG. 3 shows a peripheral shape to be referred to in the case of edge determination. Of the two surfaces sandwiching the measurement edge, the surface whose direction vector is nearly horizontal is determined to be the wall surface, and the other is determined to be the upper surface. Also, the first plane on the extension of the horizontal vector orthogonal to the edge from the point where the edge was picked is defined as the facing plane, and the distance from the intersection of the horizontal vector and the facing plane is defined as the width. The first surface on the extension of the vector going downward along the wall surface from the pick point is defined as the bottom surface, and the Z coordinate difference between the intersection and the pick point is defined as the depth. The downward vector is obtained from the cross product of the normal vector of the wall surface and the tangent vector of the edge. Depending on the shape of the object to be measured, there is a possibility that it cannot be obtained because the facing surface and the bottom surface do not exist.

When the edge is a circular arc, or when the wall is not parallel to the wall even if it is a straight line, it is assumed that the width value cannot be determined accurately. Similarly, when the bottom surface is not a plane or is inclined even if it is a plane, the depth value cannot be accurately obtained. However, it seems that there is no problem in using the width and depth values as reference values for determining measurement conditions without using them as calculated values.

The method for determining the lighting conditions is shown in the flowchart of FIG. The angle of the inclined illumination was fixed at about 45 °, and only the illuminance was set. If there is no bottom surface at the measurement point, use the standard value of transmitted illumination. This case is the best condition for edge measurement. In the case of a small round deep hole, the vertical falling illumination is 70% of the standard value, and the inclined illumination is 70% in all directions.

The determination of the deep hole is such that depth> width, where the 45 ° oblique illumination does not reach the bottom surface. The standard value of the vertical diagonal illumination is used for the narrow deep groove, and the inclined illumination in the direction perpendicular to the edge is illuminated at 70% from the left, right, front and rear directions. This is a condition under which the contrast is enhanced by the shadow and the gloss of the edge in the groove. In other cases, irradiation is performed with a standard value of vertical illumination and a standard value of oblique illumination from a direction opposite to the direction of the edge wall surface.

The image processing tools to be arranged on the measurement screen are:
Standard position and standard width
The length is set. However, if the tool shape protrudes from the range of the upper surface or the range of the shadow, it is necessary to correct them. Therefore, a suitable position and shape are reset by referring to the model shape and the shadow created by the illumination. Thus, it is possible to avoid a mistake in measuring another adjacent edge.

Image processing conditions are set so that processing is started from the shadow side and edges are searched in order to avoid erroneous recognition of edges due to dust and scratches. In addition, by effectively setting the function of removing an abnormal point, it is possible to remove data obtained by measuring burrs and the like.

Next, a simulation of a measured image will be described. The CAD rendering function simulates shadows by applying the same illumination to the three-dimensional model as the illumination conditions at the time of measurement. The display range of the model is the same as the field of view at the time of measurement, and the tool shape is displayed in an overlapping manner. This simulation makes it possible to verify the set lighting conditions and the arrangement of tools in advance.

FIG. 5 shows the result of the simulation.
The box tool automatically arranged on the linear element and the camera field of view at the time of measurement are represented by rectangles. The image processing tool can also be edited on this screen. The box tool displays the three sides of the rectangle so that the direction of image processing can be understood. Image processing is performed from the non-displayed one side to the opposite side to obtain point coordinates on the edge. Edit the position, width and length of the tool by sliding the scroll bar of the dialog box or entering a numerical value. Changing the position changes the field of view. From this figure, the width and length can be edited while confirming that the edge does not interfere with the brightness of the edge or the edge of another element.

<Measurement of Step> Teaching for step measurement was performed and the measurement was performed. And it was confirmed that automatic measurement was possible. Illumination conditions were such that a standard value was used for illuminance in vertical irradiation for all measurement points. Since the entire measurement object was the same color, there was no need to change the lighting. In the case of a measurement object having a partially different color or material, it is assumed that the setting is changed with reference to the result of the simulation or the like.

FIG. 6 shows a comparison between the simulation image (a) and the actually measured image (b). The major difference between the two is that the actual measurement image focuses only on the surface at the height to be measured due to the depth of focus, whereas the simulation shows that all surfaces are clearly visible. Also, the roughness of the machined surface is not simulated. It can be seen that a surface tool for image processing is arranged at the center, and its position and shape are simulated with good accuracy. The time required to calculate the shading and display it on the screen was 10 seconds or more. Higher-speed computers can be used to display images at higher speeds.

<Measurement of Edge> Teaching for edge measurement was performed and measurement was performed. And it was confirmed that automatic measurement was possible except for a part. As the lighting conditions, values automatically set from the shapes of all the measurement points were used as they were.

FIG. 7 shows an example in which a small deep hole is measured with a circular tool. FIG. 7 shows a simulation image (a) and an actual measurement image (b). It can be seen that the upper surface is brightened by the oblique illumination, and the bottom surface where light does not reach is darkened, so that the edge contrast is enhanced and image processing is performed with high accuracy. In the figure of the actual measurement image (b), a mark indicated by a + mark indicates an actually measured point at the edge portion. FIG. 8 shows an example in which a straight edge of a narrow deep groove is measured with a box tool. FIG. 8 also shows a simulation image (a) and an actual measurement image (b).
It can be seen that the edges are emphasized by oblique illumination from the left and right. Also in this case, the measurement points are obtained by performing image processing at intervals of 5 pixels, and are indicated by small + marks in the measurement image. It is also possible to confirm the position where the data is removed as determined as an abnormal point.

FIG. 9 shows an example in which the edge of a pin is measured with an arc tool. FIG. 8 also shows a simulation image (a) and an actual measurement image (b). Image processing is started from a shadow portion formed on the opposite side by irradiating oblique illumination from one side. Under these measurement conditions, there were portions where it was difficult to automatically determine a stable edge. Automatic operation is stopped halfway because the measurement point cannot be obtained. In this state, the operator visually judges the edge, and inputs a measurement point by manual operation. Thereafter, automatic measurement is started.

In particular, when the edge is sagged on the surface subjected to the electric discharge machining at the time of machining the mold, it is difficult to make the automatic judgment. Sometimes the traces of sparks shine and are mistaken for edges.
Conversely, a stable determination can be made on a cut or ground surface. However, since the processing method cannot be specified from the CAD data, the measurement condition must be changed by the operator.

[0047]

[Operation Procedure 1] The procedure of a specific operation example in the present invention will be described below. The example which performed teaching by the image measurement support system is shown. First, a three-dimensional CAD is started as a preparation, and data of a measured object is read. Activate the image measurement support system of the present invention. The image displayed at this time is as shown in the screen diagram of FIG. (B) shows a form of the edge image measurement support system indicating selection of a specific geometric shape.

Then, as an initial setting, the luminous intensity of the six lighting devices is designated from 0% (off) to 100%. The ideal specified value changes depending on the material and color of the measured object. If the ideal value is unknown, an appropriate value is temporarily set. FIG. 11 shows the setting screen, and numerical values are appropriately entered in the corresponding form on the left of the screen.

Next, as other initial settings, image processing conditions, lens magnification, and standard tolerance are specified. FIGS. 12A and 12B show that those conditions are specified. Next, the reference coordinate system (origin and X
Axis and Y-axis direction) are specified on the CAD, and then the same coordinate system is specified on the measuring machine. FIG. 13 is an image showing the designated coordinate lines.

Next, as a measurement procedure, a part to be measured is enlarged and displayed on the CAD, and a straight or circular edge is selected by clicking with a mouse. In the case of step measurement, a plane of that height is selected. FIG. 14 is an image in which the designated portion is enlarged. Then, an edge measurement or a step measurement in the measurement is selected from the menu of the image measurement support system. In addition, as internal processing of the image measurement support system, the shape data of the selected edge is taken in, and the shape around the selected edge is automatically determined to determine the presence / absence of the bottom face and the facing face in the figure below and the distance to the face. FIG. 15 is a diagram (a) showing a characteristic portion of the shape, and a form (b) below the diagram is distance data in the diagram (a).

Next, the ratio of each illumination to the initial value is obtained from the object to be measured and its surroundings by the flow shown in FIG. 4, and the intensity of each illumination is automatically determined.

The flow shown in FIG. 4 will be described. First, as for the planar step, the type of illumination is selected at a rate of 100% (percent vertical illumination). Next, when there is no bottom surface, the transmission illumination is set to 100%. For a small round hole with a small diameter, the ratio of vertical falling illumination is set to 70 (%), and the inclination illumination is set to 70% from all directions.

For deep and narrow grooves, the ratio of vertical falling illumination is set to 100 (%), and the inclination illumination is set to 70% from both sides. For the other edges, the ratio of vertical falling illumination is set to 100 (%), and tilted illumination is set to 10
Set to 0%.

Next, a necessary item is selected as a measurement result, and a comparison with a tolerance is designated. For other than standard tolerance, enter the tolerance value directly. FIG. 16 shows the input screen.

The above procedure is repeated for each part to be measured. Finally, save the above measurement procedure in a file.

[0056]

[Operation Procedure 2] Next, a specific description will be given of the verification method of the present invention.

After selecting a portion to be verified on the measurement procedure editing screen of the image measurement support system and selecting an image processing tool, a simulation of an image at the time of measurement is displayed. The range of the image to be captured and the shape of the image processing tool are displayed so as to be superimposed on the bright and dark image formed on the measurement object by the illumination.
FIG. 17 is an image in which the range of the captured image and the shape of the image processing tool are displayed in an overlapping manner.

Here, it is visually confirmed that the edge of the object to be measured has a clear contrast between light and dark due to illumination. Also, make sure that the image processing tool has an appropriate position and size with respect to the edge. If it is not appropriate, the position and size of the lighting and the tool are changed, and displayed again to find a suitable condition.

The saved measurement procedure file is read into the image measurement support system. If you want to change the default lighting,
The measured object is actually illuminated, and an appropriate value of each illumination is experimentally obtained, and reset in a dialog box. When the setting is changed from the initial value to the resetting, the setting is reflected in all the taught measurement procedures. The data of the created measurement procedure is converted into a part program for a vision measuring instrument and output. FIG. 18 shows a display image for conversion into a part program.

Then, the part program is transferred to a control personal computer of the measuring instrument via a floppy (registered trademark) disk or a LAN.

Further, the object to be measured is fixed to the measuring machine, and the reference plane for the measurement and the coordinate system in the reference axis direction are manually set.
Then, the part program is executed, and the control personal computer measurement results automatically measured by the measuring machine are sequentially displayed. After the automatic measurement is completed, save the measurement results in a file,
The operator checks the result.

[0062]

As described above, the present invention is effective in reducing the number of man-hours for off-line teaching work and improving the operating rate of a measuring machine. In particular, in the inspection of a trial product such as a resin molding or a precision press, it becomes possible to prepare for the measurement in parallel with the processing of the mold, and the automatic measurement can be started as soon as the trial product is completed.

The purpose of the present invention is to provide means for verifying the determined conditions in advance by performing a simulation and improving the reliability of automatic measurement. Automatically determine the lighting conditions suitable for image measurement and enable offline teaching. Another object of the present invention is to provide a means for verifying the determined conditions in advance by simulating the illumination and improving the reliability of the automatic measurement. Then, the measurement can be automatically started as soon as the trial product is completed. In the case where measurement is performed in an automated line, teaching can be performed without stopping the line.

In the actual measurement of the measured object, the inspector only needs to consider only the rejected data after the automatic measurement, and the efficiency is greatly improved. If the values of the roundness and straightness are output in advance, there is an advantage that, when checking the reliability of the data after the automatic measurement, a measurement error due to adhesion of burrs or dust can be easily found.

[Brief description of the drawings]

FIG. 1 is a screen view showing an image of CAD data of a mobile phone.

FIG. 2 is a screen diagram of a standard value setting dialog box for lighting conditions displayed on a monitor screen.

FIG. 3 is a schematic diagram of peripheral shape data of a specific portion of a measurement object.

FIG. 4 is a flowchart showing a procedure for determining an illumination condition.

FIG. 5 is a screen view of a simulation of a measurement image.

FIGS. 6A and 6B are screen views of (a) a simulation image and (b) an actual measurement image of step measurement.

7A and 7B are screen views of (a) a simulation image and (b) an actual measurement image of edge measurement of a small-diameter deep hole.

FIGS. 8A and 8B are screen views of (a) a simulation image and (b) an actual measurement image of edge measurement of a narrow deep groove.

9A and 9B are screen views of a simulation image and a measurement image of a pin edge measurement, respectively.

FIG. 10A shows a three-dimensional image of CAD data;
(B) Each screen view showing a selection form of the image measurement support system.

FIG. 11 is a screen view showing a designated value writing form.

12A is a screen view showing a writing form of illumination luminous intensity and FIG. 12B is a writing form of ordinary tolerance.

FIG. 13 is a screen view of a simulation image of a reference coordinate system setting.

FIG. 14 is a screen view of a simulation image showing a state in which a measurement portion is enlarged and displayed.

15A is a schematic diagram of data on a peripheral shape of a specific portion of a measurement object, and FIG. 15B is a screen diagram of a measurement image showing measurement distance data.

FIG. 16 is a screen view showing a form for writing a tolerance value for element measurement.

FIG. 17 is a screen diagram of a simulation image of a measurement portion.

FIG. 18 is a screen view showing a writing form for reading a file.

Claims (3)

[Claims] 1. A first step of setting a standard value of illuminance of each of a plurality of lighting devices provided in an image measuring device toward a measured object from data of an actual color and a material of the measured object;
Setting the illuminance of each of the lighting devices as a ratio to the standard value set in the first step, in accordance with the characteristic geometric shape of the part to be measured, based on the three-dimensional CAD data of the measurement object; An offline teaching method for an image measuring device by optimizing lighting conditions, comprising the steps of: 2. A method for responding to a characteristic geometric shape of a portion for measuring the illuminance of each lighting device in the second step,
2. The illumination condition according to claim 1, wherein the measurement is performed by an image measurement support system including an image processing tool having a measurement function specialized for the geometric feature and a boundary determination function for determining a boundary of a specific shape. Offline teaching method of vision measuring machine by optimization. 3. The method according to claim 2, wherein the coordinates of the three-dimensional CAD data of the measured object are superimposed so that the actual measured object is located at the same position as that measured by the image measuring device, and the same as each lighting device. A third step of setting virtual light source coordinates at the coordinate position, and shading on each part of the measured object of the three-dimensional CAD data by the rendering function of the CAD system based on each light source at the coordinates with the set illuminance of each lighting device. The fourth step of outputting and displaying a shaded image expressed as if the image were given, and selecting the shaded image of the portion to be verified on the measurement screen of the image measurement support system by selecting the optimality of the set lighting conditions on the measurement screen. A fifth step of selecting a specific shape from the image processing tools provided in the measurement support system and displaying the selected shape over the shadow image, and checking the conditions under which the edge portion of the measurement target is set. Visually confirming the clarity of the contrast between light and dark and the accuracy of the position and size of the edge with the above-mentioned shadow image, and if it is confirmed that it is inappropriate, change the setting of the lighting conditions and the position and size of the image processing tool. A sixth step of redisplaying the shaded image under the corrected setting conditions, visually confirming this, and setting the optimum lighting conditions, comprising the steps of: Teaching method.