JP7431195B2 - Inspection device for planar shape measurement system - Google Patents

Description

Embodiments of the present invention relate to an inspection device for a planar shape measurement system that measures the planar shape of a strip steel plate transported in steel manufacturing equipment.

Planar shape measurement systems are known that measure the surface wave height, steepness, elongation rate, etc. of a steel strip by irradiating a slit-shaped light onto the steel strip being conveyed on a steel rolling line (for example, patented Reference 1 etc.).

Such a planar shape measuring system includes a light source, an imaging device, and a planar shape measuring device. The light source irradiates the strip-shaped steel plate with slit-shaped light. The imaging device captures an image of the surface of the strip steel plate irradiated with the slit-shaped light and outputs image data. The planar shape measuring device performs image processing on the output image data, performs coordinate transformation processing, etc. on the image-processed data, calculates and outputs various numerical values representing the planar shape of the steel strip.

Planar shape measurement systems are inspected regularly or irregularly to confirm their soundness. A typical inspection method for a planar shape measurement system is to use a corrugated plate for inspection whose surface wave height, wave pitch, etc. are predefined. The inspection corrugated plate is fixed within the measurement area of the planar shape measurement system, and its surface is irradiated with slit-shaped light. The planar shape measuring device acquires image data of the surface of the corrugated sheet for inspection and calculates a numerical value representing the surface shape of the corrugated sheet for inspection. The calculated and output data regarding the surface shape is compared with the reference value of the inspection corrugated plate, and it is determined whether the measurement by the planar shape measurement system is sound.

Since the inspection corrugated plate serves as a reference for measurement, it is necessary to strictly define its surface shape. Therefore, the inspection corrugated plate must be made of a metal material and be heavy. Further, when the inspection corrugated plate is placed in the measurement area, its longitudinal dimension is limited so that it does not deform. The measurement area is the width of the rolling line where the planar shape measurement system is installed, and may be several meters long. In such cases, multiple inspection corrugated plates must be precisely aligned and fixed across the measurement area. There is.

Arranging and fixing the above-mentioned inspection corrugated plates every time an inspection is performed is inefficient and requires a great deal of labor and time, and improvements are needed.

In addition, with the above-mentioned inspection method, it is possible to detect the presence or absence of an abnormality from the output value of the planar shape measuring device, but it has been pointed out that it is not easy to investigate where in the planar shape measuring system the cause of the abnormality is. There is.

Japanese Patent Application Publication No. 2012-251816

An object of the embodiments of the present invention is to obtain an inspection device for a planar shape measuring system that can easily inspect the planar shape measuring system.

An inspection device for a planar shape measuring system according to an embodiment of the present invention is installed on a plane including a first direction, which is the conveyance direction of the steel plate when the object to be measured is a steel plate, and a second direction orthogonal to the first direction. a light projector installed to irradiate two parallel slit-shaped lights orthogonally to the first direction onto the surface of the object to be measured in the measurement area; and the object to be measured in the measurement area. an imaging device installed to take an image of the entire surface of the object from an upstream diagonal direction or a downstream diagonal direction of the first direction; and a reflection image of the surface of the object to be measured taken by the imaging device. Convert the bright lines of data corresponding to each of the two parallel slit-shaped lights into data of coordinates in a third direction orthogonal to the first direction and the second direction, which are associated with the coordinates in the second direction. and output as first surface height data of the object to be measured, and based on deviation data of the first surface height data for each bright line, second This is an inspection device for a planar shape measuring system including a planar shape measuring device that outputs surface height data. This inspection device includes an inspection image recording means for recording and outputting the reflection image data together with the acquisition date and time, and for determining the inspection result of the planar shape measuring system based on the data output by the planar shape measuring device. and inspection determination means for outputting determination data. The object to be measured is a plate material having a length spanning the length of the measurement area in the second direction and having a flat surface, and when the object is stationary and installed in the measurement area, the planar shape measurement can be performed. This is an inspection jig installed to produce a deflection due to its own weight that can be detected by the measurement accuracy of the system. The determination data includes the amount of deflection of the inspection jig calculated and output by the planar shape measuring device.

In this embodiment, an inspection device for a planar shape measuring device that can easily inspect a planar shape measuring system is realized.

FIG. 1 is a schematic block diagram illustrating an inspection device of a planar shape measuring system according to an embodiment. FIG. 2(a) is a diagram schematically showing an example of image data. FIG. 2(b) is a schematic diagram for explaining image processing performed on the image data of FIG. 2(a). FIG. 3 is a schematic diagram for explaining the operation of the planar shape measuring device when the inspection device of the embodiment is in operation. It is an example of the typical inspection screen output by the inspection device of the planar shape measurement system of an embodiment. FIG. 3 is a schematic block diagram illustrating an inspection method of a planar shape measuring system of a comparative example. It is an example of the inspection screen output by the inspection method of the planar shape measurement system of a comparative example.

Embodiments of the present invention will be described below with reference to the drawings.
Note that the drawings are schematic or conceptual, and the relationship between the thickness and width of each part, the size ratio between parts, etc. are not necessarily the same as those in reality. Furthermore, even when the same part is shown, the dimensions and ratios may be shown differently depending on the drawing.
Note that in the present specification and each figure, the same elements as those described above with respect to the existing figures are denoted by the same reference numerals, and detailed explanations are omitted as appropriate.

FIG. 1 is a schematic block diagram illustrating an inspection device of a planar shape measuring system according to an embodiment.
In addition to the inspection device 10, FIG. 1 shows an inspection jig 1, a planar shape measuring device 20, a light projecting device 2, and an imaging device 3. The planar shape measuring device 20, the light projection device 2, and the imaging device 3 constitute a planar shape measuring system.

In the inspection device 10 of the embodiment, the inspection jig 1 is used to inspect the presence or absence of an abnormality in the planar shape measuring system including the planar shape measuring device 20. The inspection jig 1 is a plate-like member having a flat surface. The inspection jig 1 has a sufficient length across the width direction of the measurement area 1a. Therefore, by placing one inspection jig 1 once in the measurement area 1a and fixing it, the environment setting for inspection can be completed.

When the width of the measurement area 1a is, for example, 5 [m], the length in the longitudinal direction of the inspection jig 1 is about 5 [m], and preferably extends over the entire width of the measurement area 1a. It is set as follows. The length of the inspection jig 1 in the lateral direction is made long enough to irradiate two slit-shaped lights and reflect the irradiated light. The thickness of the inspection jig 1 can be set arbitrarily, but is appropriately set depending on the material and dimensions of the inspection jig 1. The irradiation surface of the inspection jig 1 is a flat surface, and is preferably surface-treated to provide sufficient brightness when the irradiation light is reflected. From the viewpoint of weight and the like, the inspection jig 1 is made of, for example, aluminum or an alloy thereof, and the surface thereof is subjected to an oxide film (alumite) formation treatment from the viewpoint of stable image formation.

The inspection jig 1 is fixed on support members 1b provided at regular intervals in the width direction of the measurement area 1a. The number of support members 1b is provided in accordance with the width of the measurement area 1a. In this example, two supporting members 1b are provided, one at each end of the inspection jig 1 in the width direction. The inspection jig 1 causes a deflection due to its own weight between the supporting members 1b, and the inspection device 10 and the planar shape measurement system measure the deflection to determine the validity of the measured value of the surface height of the inspection jig 1. Allows for determination of gender. The installation intervals of the supporting members 1b are set so that the magnitude of deflection caused by the material, shape, etc. of the inspection jig 1 can be detected with the measurement accuracy of the planar shape measuring device 20.

The inspection device 10 is connected to the planar shape measuring device 20 and the imaging device 3. The light projection device 2 irradiates the surface of the inspection jig 1 placed in the measurement area 1a with two slit-shaped lights. The imaging device 3 is provided to capture an image of the entire measurement area 1a. The imaging device 3 captures an image in which the surface of the inspection jig 1 placed in the measurement area 1a is irradiated with slit-shaped light, and converts it into image data.

Note that the measurement area 1a is a common measurement area for the normal measurement operation of the planar shape measurement system and the inspection operation by the inspection device 10, and is an area where the conveyed steel plate and the inspection jig 1 are imaged by the imaging device 3. be. More specifically, the length of the measurement area 1a in the transport direction is set so that a reflection image of two slit-shaped lights can be captured. The slit-shaped light is irradiated almost orthogonally to the transport direction. The length of the measurement area 1a in the direction perpendicular to the conveyance direction is set so as to include the reflected image of the slit-shaped light over the width of the steel plate conveyed along the conveyance direction. Hereinafter, the direction along the conveyance direction of the steel material may be referred to as the L direction, and the direction orthogonal to the L direction may be referred to as the C direction. It is assumed that the measurement area 1a is a plane including both the L direction (first direction) and the C direction (second direction). When the steel plate is conveyed, the steel plate is conveyed from the upstream side to the downstream side in the L direction.

The inspection device 10 can record image data acquired by the imaging device 3 as an inspection image, and output the recorded image together with data of previously acquired images. The operator of the inspection device 10 can visually determine whether there is an abnormality in the surface shape measurement system by displaying currently acquired image data or previously acquired image data on a monitor or the like.

The planar shape measuring device 20 is connected to the imaging device 3, and based on the image data acquired from the imaging device 3, the surface height coordinates in the width direction coordinates of the inspection jig 1 are calculated as surface height data. Calculate and output as . The inspection device 10 can use the surface height data calculated by the planar shape measuring device 20 to output a result of determining whether the calculation result by the planar shape measuring device 20 is appropriate.

In a normal measurement operation of the planar shape measurement system, image data is acquired while the steel plate is being transported and moving. The steel plate vibrates as it is transported, and the surface height data calculated from the image data includes time fluctuations due to the vibration of the steel plate. Therefore, the planar shape measuring device 20 uses surface height data based on reflected images of two slit-shaped lights that are irradiated in parallel in close proximity to each other, thereby canceling out the influence of temporal fluctuations in the coordinate data. Surface height data with variations reduced or eliminated can be calculated. The inspection device 10 can determine whether such an operation of the planar shape measuring device 20 is appropriate.

The configuration of the inspection device 10 of the planar shape measuring system according to the embodiment will be described in detail.
In explaining the configuration of the inspection device 10, the configuration of the planar shape measuring system will first be described with reference to FIG.
In a normal measurement operation of the planar shape measuring system, the planar shape of a steel plate (not shown) that has been conveyed to the measurement area 1a along the conveyance direction of the steel plate is measured. This planar shape measuring system measures the surface shape of a steel plate (not shown) using a well-known technique, as described in Patent Document 1 and the like. More specifically, the planar shape measuring device 20, the light projecting device 2, and the imaging device 3 are configured and operate as follows.

The light projection device 2 has two light sources 2a and 2b. The light sources 2a and 2b are provided at positions that irradiate substantially parallel slit-shaped light into the measurement area 1a. For example, the light sources 2a and 2b are provided diagonally above the measurement area 1a. The optical axes of the light emitted from the light sources 2a and 2b are set to intersect with the direction of conveyance of the steel plate, and preferably set to be substantially orthogonal to the direction of conveyance of the steel plate.

The imaging device 3 includes one or more cameras so as to be able to image the entire measurement area 1a. In this example, the imaging device 3 includes three cameras 3a to 3c. By combining the image data output by the three cameras 3a to 3c in the C direction, image data of the steel plate covering the measurement area 1a in the C direction can be obtained. Cameras 3a to 3c are provided diagonally above the measurement area 1a. In order to measure the height of the surface of the steel plate on the measurement area 1a, the optical axes of the cameras 3a to 3c are provided at an angle from the C direction. The angle from the C direction may be set on the upstream side of the L direction, or may be set on the downstream side of the L direction.

In the imaging device 3, reflected images of the two slit-shaped lights irradiated onto the surface of the steel plate are captured by the cameras 3a to 3c, and are transmitted to the planar shape measuring device 20 as image data. The imaging device 3 captures reflected images of the two slit-shaped lights multiple times. The number of times of imaging is set in advance, and, for example, image data is acquired over several frame periods of the cameras 3a to 3c. To explain with a more specific example, the cameras 3a to 3c continue to acquire image data with a frame period of 60 Hz for 10 seconds, and each acquires 600 pieces of image data. Each image data is associated with the acquisition date and time of the data.

The surface coordinate conversion unit 22 receives image data acquired by the cameras 3a to 3c, and executes coordinate conversion of the slit-shaped light for each image data. The coordinate-converted data is output as surface height data associated with the coordinates in the C direction. Note that in the normal operation of the planar shape measuring device 20, the steel plate is transported in the L direction, so the data on the surface height of the slit-shaped light extending in the C direction also includes the coordinates of the steel plate in the L direction.

The surface coordinate conversion unit 22 outputs the surface height data of the two slit-shaped lights as a set of surface height data. The uneven shape calculation unit 24 receives a set of surface height data for each slit-shaped light and calculates a deviation of the set of surface height data. The unevenness calculation unit 24 sequentially integrates and arranges the deviations of a set of surface height data in the order of associated date and time data, and outputs the results as surface shape map data. In addition, in the normal operation of the planar shape measuring device 20, since the coordinates of the steel plate in the L direction change at each time, the unevenness shape calculation unit 24 calculates the amount of time variation reduced over the C direction coordinate x the L direction coordinate. , the data of the surface shape map, which is the data of the two-dimensional surface height of the steel plate, will be output.

The uneven shape calculating section 24 can calculate the surface shape of the steel plate, such as the surface wave height, based on the data of the surface shape map, and can output the results.

The measurement result display unit 26 outputs surface shape map data and surface shape data in a desired format.

In the inspection operation using the inspection device 10, the planar shape measurement system is set to perform the above-described operation over a preset period. That is, in the inspection operation, the inspection device 10 acquires data from the imaging device 3 and the planar shape measuring device 20 based on the operations of the above-mentioned parts by operating the planar shape measuring system. Based on the acquired data, the inspection device 10 calculates and outputs data for determining whether each part is operating properly.

The configuration of the inspection device 10 will be explained.
In the inspection of the surface shape measurement system using the inspection device 10, instead of the steel plate being conveyed in the L direction, the inspection jig 1 is placed and fixed in a stationary state over the C direction of the measurement area 1a. As described above, the inspection jig 1 is provided so as to generate a deflection that can be sufficiently detected with the measurement accuracy of the planar shape measurement system. The inspection device 10 includes an inspection image recording section 12 and an inspection determination section 14. The inspection device 10 further includes an inspection result display section 16.

The inspection image recording unit (inspection image recording means) 12 acquires image data from the imaging device 3. The image data acquired from the imaging device 3 is image data including a reflected image of two slit-shaped lights irradiated onto the surface of the fixed inspection jig 1. The inspection image recording unit 12 records image data together with the date and time of acquisition of the image data. The inspection image recording unit 12 records image data associated with the acquisition date and time of the image data, and can output desired image data together with, for example, the data acquisition date and time based on an operator's designation.

The inspection image recording unit 12 preferably has image processing and calculation functions for the acquired image data. The inspection image recording unit 12 performs image processing on the acquired image data, calculates and outputs data regarding the reflected image of the slit-shaped light. The operator of the inspection device 10 can display the image data of a desired date and time and output the image processing calculation result of the image data. Therefore, the operator can visually judge the image data and its image processing calculation results, and can detect abnormalities in the system that generates image data or the system that acquires image data, such as the light projector 2 or the imaging device 3. The presence or absence can be determined.

The inspection determination unit (inspection determination means) 14 acquires surface coordinate data for each slit-shaped light associated with the C direction coordinate from the surface coordinate conversion unit 22 as surface height data (first surface height data). do. The inspection determination unit 14 calculates data for determining the validity of the measurement based on the surface height data, and outputs the result.

The inspection determination unit 14 acquires data on the deviation of the surface heights of the two slit-shaped lights from the uneven shape calculation unit 24 . The inspection determination unit 14 can determine the validity of the measurement by determining the validity of the data of the surface height deviation in the C direction.

The data for determining the validity of the measurement by the inspection determination unit 14 include, for example, the measured value of the width of the inspection jig 1, the validity rate of surface height data, the validity rate of surface height deviation, and imaging data. stability and the amount of deflection based on the surface height data of at least one of the two slit-like lights.

In this example, the measured width of the inspection jig 1, the effective rate of the surface height, the stability of the imaged data, and the amount of deflection are calculated based on the surface height data output across the C direction. The surface height data in the C direction is output from the surface coordinate conversion section 22.
In this example, the effective rate of the surface height deviation is calculated based on the data of the surface height deviation output over the C direction. Data on the deviation of the surface height in the C direction is output from the unevenness shape calculation section 24.

Here, the effective rate of surface height data is defined as valid when the surface height data at each coordinate in the C direction is within a predetermined range for each of the two slit-shaped lights, and the number of valid coordinates. It is the ratio of the number of coordinates to the total number of coordinates in the C direction.

In addition, the effective rate of deviation is defined as valid when the surface height deviation data at each coordinate in the C direction of two slit-shaped lights is within a predetermined range, and all coordinates in the C direction of the number of valid coordinates. It refers to the proportion to a number.

Further, the stability of imaging data refers to the standard deviation of surface height data of imaging data for a predetermined number of times (for example, 600 times) for at least one of the two slit-shaped lights. At this time, one or more coordinates of the surface height in the C direction are set in advance, and the standard deviation is determined for each coordinate.

In addition, the amount of deflection is the center of a straight line connecting the surface height coordinates at the coordinates at 1/2 of the coordinates at both ends in the C direction (referred to as center coordinates) and the surface height coordinates at both ends in the C direction. It refers to the difference in surface height coordinates.

The inspection result display unit 16 converts the data output by the inspection image recording unit 12 and the inspection determination unit 14 into a predetermined format according to the operator's specifications, and displays the data on a display device (not shown) such as a monitor. Display the data.

In addition, as in this example, the inspection result display section 16 inputs the surface height data obtained by the two slit-shaped lights output from the surface coordinate conversion section 22, and displays it over, for example, the C direction. It can also be displayed as the deflection of the jig 1 in the C direction.

Further, as in this example, the inspection result display section 16 develops the data (second surface height data) output from the unevenness shape calculation section 24 in time series and outputs it as surface shape map data. be able to. Since the inspection jig 1 is stationary, the data of the surface shape map at this time is outputted as pseudo two-dimensional data by executing a time variation removal calculation for the same L direction coordinate. By visually inspecting this two-dimensional data, the operator can determine whether or not there is an abnormality in the processing of the uneven shape calculation section 24 or the like.

The usage and operation of the inspection device 10 of the embodiment will be explained.
The inspection operation of the inspection device 10 of the embodiment includes a preparation stage and an inspection operation stage. The inspection operation phase is carried out after the preparatory phase has ended.

In the preparation stage, the inspection jig 1 is installed in the measurement area 1a. As described above, the inspection jig 1 is placed and fixed across the measurement area 1a in the C direction. Note that the reference value of the amount of deflection is measured and set in advance. The reference value of the amount of deflection may be measured using another measurement system, or may be measured by this inspection device 10 and the surface shape measurement system. Further, the inspection device 10 may be configured to record past measured values, and the inspection device 10 can perform comparisons between measured values and past measured values as well as comparisons between measured values and predetermined reference values. The reference value or the past measured value may be selected.

In the inspection device 10, reference values and the like for determining other inspection data are set in advance.
Note that the reference value for determining the validity of inspection data including the amount of deflection may be determined by using previously measured data, or by statistically processing values that have been measured and calculated in the past. It may also be used as a reference value.

The light projection device 2 is set so that the surface of the inspection jig 1 is irradiated with two slit-shaped lights. The imaging device 3 is set to take an image of the inspection jig 1 within the measurement area 1a.

In this state, the inspection operation step is performed. In the inspection operation stage, the inspection device 10, the light projection device 2, the imaging device 3, and the planar shape measuring device 20 are operated, and the inspection device 10 collects necessary data, performs arithmetic processing, etc., and outputs it.

A method of measuring and calculating inspection data of the inspection device 10 will be explained.
First, a method of measuring and calculating inspection data by the inspection image recording section 12 will be explained.
FIG. 2(a) is a diagram schematically showing an example of image data. FIG. 2(b) is a schematic diagram for explaining image processing performed on the image data of FIG. 2(a).
FIG. 2A schematically shows an example of image data DI1 including two bright lines G1 and G2 of slit-like light.
As shown in FIG. 2A, the image data DI1 includes pixel data in a two-dimensional manner, and two-dimensional coordinates are expressed in the row direction and column direction of the image data DI1. The pixel data includes data representing the magnitude of brightness. In this example, it is assumed that the pixel data is arranged at approximately equal intervals in the row direction and constitutes column data. Column data R1 to Rn are arranged at approximately equal intervals in the column direction. Note that since the imaging device 3 captures the reflected image from a position angled toward the upstream side (or downstream side) in the row direction, the bright lines G1 and G2 are bright lines running in an oblique direction on the image data DI1. The image was taken as

When the inspection image recording unit 12 acquires such image data, it calculates the distribution of luminance data for each of the column data R1 to Rn.
In FIG. 2(b), brightness data BR1 corresponding to column data R1 and brightness data BR2 corresponding to column data R2 are shown, and thereafter, brightness data BRn corresponding to n-th column data Rn is shown. It is shown. In each of the brightness data BR1 to BRn in FIG. 2(b), the vertical axis represents coordinates in the row direction, and the horizontal axis represents the magnitude of brightness.

As shown in FIG. 2(b), in one column data, the magnitude of the luminance corresponding to the coordinates of the two points having the maximum luminance corresponds to the magnitude of the luminance of the luminance lines G1 and G2. . For example, in the brightness data BR1, BG11 and BG21 represent the magnitude of brightness corresponding to the bright lines G1 and G2, respectively, and this is called the maximum brightness point. The inspection image recording unit 12 calculates the average value of the brightness of the maximum brightness point of the bright line G1 and the brightness of the bright line G2 by adding the magnitude of the brightness of the maximum brightness point for each bright line in the column direction and dividing the result by the number of columns. Calculate and output the average value of the brightness at the maximum brightness point.

In the range between the maximum brightness points, that is, in FIG. 2B, the brightness of the area surrounded by a circle represents a dark area that separates the two bright lines G1 and G2, and is called a bright line separation area. In the figure, the brightness levels of the bright line separation regions are expressed as BD1 to BDn. The inspection image recording unit 12 calculates the average value of the brightness of the bright line separation area between the bright lines G1 and G2 by adding the brightness magnitudes BD1 to BDn of the bright line separation area in the column direction and dividing by the number of columns. Calculate and output.

In this way, the average value of the brightness at the maximum brightness point of each of the bright lines G1 and G2 and the average value of the brightness of the bright line separation area between the bright lines G1 and G2 are calculated and output for each image data. Therefore, the acquired image data includes, in addition to the date and time of image data acquisition, the average value of the brightness of the maximum brightness point for each bright line G1 and G2, and the average value of the brightness of the bright line separation area between the bright lines G1 and G2. Data is associated and recorded.

The data output by the inspection image recording section 12 is displayed via the inspection result display section 16 and the display device. The operator of the inspection device 10 can visually check these data displayed on the display device to determine whether there is an abnormality. The data output by the inspection image recording unit 12 is image data obtained by capturing an image of the surface of the inspection jig 1 captured by the imaging device 3. Therefore, by checking these data, the operator can determine whether there is an abnormality in the imaging device 3, such as a failure in one of the cameras 3a to 3c or an abnormality in either the light sources 2a or 2b.

Specifically, if the image data is completely black, completely white, or the brightness data is zero or an abnormal value, which of the cameras 3a to 3c corresponding to the image data is There may be an abnormality in the crab.
Alternatively, if there is only one bright line in the image data, it is possible that there is an abnormality in the other light source of the light sources corresponding to the bright line.
Furthermore, in addition to the currently acquired data, the operator can output and display previously acquired data at the same time, allowing the presence or absence of anomalies to be detected by relative comparison with past data. becomes possible.

Next, a method of measuring and calculating inspection data by the inspection determining section 14 will be explained.
The inspection determination unit 14 acquires data on the calculated surface height through coordinate transformation for each two slit-shaped lights from the surface coordinate transformation unit 22 of the planar shape measuring device 20 .
FIG. 3 is a schematic diagram for explaining the operation of the planar shape measuring device when the inspection device of the embodiment is in operation.
FIG. 3 schematically shows the relationship between the image data input to the surface coordinate conversion section 22 and the surface height data output from the surface coordinate conversion section 22.
The diagram at the top of the arrow in FIG. 3 schematically represents image data DI1 to DI3 captured by three cameras 3a to 3c, respectively. Bright lines G1 and G2 in the image data DI1 to DI3 represent reflected images of slit-shaped light. In this example, the cameras 3a to 3c are arranged at an angle from the direction C, so the bright lines G1 and G2 are recorded as oblique bright lines in the image data.
The diagram at the bottom of the arrow in FIG. 3 schematically represents the surface height data output by the surface coordinate conversion section 22. In this figure, the horizontal axis represents the coordinates in the C direction, and the vertical axis represents the coordinates representing the surface height. In this example, the bright lines G1 and G2 are shown to have different surface heights.

The surface coordinate conversion unit 22 of the planar shape measuring device 20 inputs the image data DI1 to DI3, performs coordinate conversion, and outputs surface height data of the bright lines G1 and G2 associated with the C direction coordinates. The inspection determination unit 14 acquires data on the surface heights of the bright lines G1 and G2 from the surface coordinate conversion unit 22. The inspection determination unit 14 calculates the distance between the coordinates E1 and E2 of the ends of the bright lines G1 and G2, and outputs it as a measured value of the width of the inspection jig 1. The inspection determination unit 14 already has a reference value for the width of the inspection jig 1, and outputs the measured width data of the inspection jig 1 and the reference value. By determining whether there is a deviation between the measured value and the reference value, it is possible to determine whether the surface coordinate conversion section 22 is operating appropriately.

The inspection determination unit 14 determines whether or not the surface height data of each of the bright lines G1 and G2 is within a predetermined range for each coordinate in the C direction. In the figure, a predetermined range is shown as a lower limit value LL to an upper limit value UL. The inspection determination unit 14 determines the surface height data by dividing the number of coordinates having valid data by the total number of coordinates in the C direction, assuming that the data is valid when the surface height data is within a predetermined range. Calculate the effectiveness rate. In the case of the example shown in FIG. 3, the number of data for the surface height of the bright line G1 is the number of coordinates between the coordinates E1 and E2 of the end. The purpose of the surface height data being within a predetermined range is to exclude data having abnormal values. In other words, there are cases where brightness data is lost due to image processing, coordinate transformation, etc., and when such abnormal data is sufficiently small, it is possible to determine that the operation of the surface coordinate transformation unit 22 is appropriate. Become.

The inspection determination unit 14 calculates the deviation of the surface height data of each of the bright lines G1 and G2 for each coordinate in the C direction. The deviation of the calculated surface height data for each coordinate in the C direction is valid within a predetermined range, and the surface height can be calculated by dividing the number of valid coordinates by the total number of coordinates in the C direction. Calculate the effective rate of deviation of the data. Even if the surface height data of the two bright lines G1 and G2 at the same coordinates are within the normal range, when the deviation is calculated, it may become abnormal, and if there are many abnormalities, It is useful to detect and judge such an abnormality in advance, since it will affect the calculation result of the surface shape map by the unevenness shape calculation section 24. In this example, it is assumed that the deviation data of the surface height data is acquired from the unevenness shape calculation section 24, but the inspection determination section 14 uses the deviation data of one set of surface coordinates output from the surface coordinate conversion section 22. The deviation of the height data may also be calculated.

The inspection determination unit 14 calculates and outputs the stability of the image data. As described above, the stability of the imaging data is calculated by calculating the fluctuation of the surface height data over, for example, several frames of the imaging device 3. Since the inspection jig 1 is sufficiently long in the C direction, if there is vibration etc. when the inspection jig 1 is installed, it will be difficult to obtain accurate data and perform the inspection. This is done to understand the measurement status.

The inspection determination unit 14 calculates the amount of deflection of the inspection jig 1 and compares it with a preset reference value to determine whether the operation of the surface coordinate conversion unit 22 is being performed appropriately. I can do it.

FIG. 4 is an example of a schematic inspection screen output by the inspection device of the planar shape measurement system according to the embodiment.
FIG. 4 shows an example of the inspection screen 50 displayed on the display device.
As shown in FIG. 4, the inspection screen 50 includes a C-direction deflection graph display section 51, a surface shape map graph display section 52, an image data display section 53, and a measurement result display section 54 in this example. Needless to say, it is possible to arbitrarily select appropriate graphs and data as to how to arrange them.

In the C-direction deflection graph display section 51, the inspection result display section 16 displays surface height data across the C direction of the inspection image acquired during the inspection in the form of a graph. In this example, the data for graphing is output from the surface coordinate conversion section 22, and is displayed by the inspection result display section 16 processing the data.
In the surface shape map graph display section 52, the data calculated by the unevenness shape calculation section 24 is displayed as a two-dimensional graph by the inspection result display section 16. Data for graphing is output from the unevenness shape calculation unit 24, and is displayed by processing the data in the inspection result display unit 16.

The image data display section 53 displays image data acquired during the inspection. In this example, image data captured by cameras 3a to 3c (in the figure, CAM1 to CAM3 correspond to cameras 3a to 3c, respectively) is displayed on the inspection image display section 53a, and at the same time, past image data selected by the operator is displayed. can be displayed on the recorded image display section 53b.

In the displayed image data, the average value of the brightness of the maximum brightness point and the average value of the brightness of the bright line separation area associated with the image data are displayed simultaneously. For example, out of 240/240/30 of CAM1, "240/240" indicates the average value of the luminance of the two bright lines G1 and G2, and "30" indicates the bright line separation area. represents the average value of brightness.

The measurement result display section 54 shows a measured value 54a of the width of the inspection jig 1 as the measurement plate width. Further, as the width effective rate, a calculated value 54b of the effective rate of the surface height over the C direction of the image data acquired at the time of the inspection is displayed. As the length effective rate, a calculated value 54c of the effective rate of the deviation of the two surface heights of the image data acquired at the time of the inspection is displayed. Furthermore, as the L-direction stability, a calculated value 54d of the stability of the imaging data at the time of the inspection is displayed. A measured value 54e of the amount of deflection in the C direction at the time of the inspection is displayed together with a reference value 54f.

The operator of the inspection device 10 visually checks the image data on the image data display section 53 and determines whether or not there is an abnormality in the light projection device 2 or the imaging device 3. The operator of the inspection device 10 also visually checks the C-direction deflection graph display section 51, the surface shape map graph display section 52, and the measurement result display section 54 to determine whether or not there is an abnormality in the planar shape measuring device 20.

In this way, the inspection device 10 of the planar shape measurement system is operational and ready for use.

The effects of the inspection device 10 of the planar shape measuring system according to the embodiment will be explained with reference to a comparative example.
FIG. 5 is a schematic block diagram illustrating an inspection method for a planar shape measuring system of a comparative example.
As shown in FIG. 5, the planar shape measuring system includes a light projecting device 2, an imaging device 3, and a planar shape measuring device 120, and measures the surface height of the inspection corrugated plate 101 and compares it with a reference value. By doing so, the presence or absence of an abnormality in the planar shape measurement system can be checked.

The configurations of the light projecting device 2 and the imaging device 3 are the same as those in the above-described embodiment, and their explanation will be omitted. The inspection corrugated plate 101 has a width shorter than the width of the measurement area 101a, and is made of a metal material. It is thick enough and heavy to prevent deformation and maintain its surface shape.

If the width of the inspection corrugated plate 101 can only cover the imaging area of one camera in the measurement area 101a, install as many inspection corrugated plates 101 as the number of cameras, or It is necessary to shift the position in the width direction and repeat the inspection work for the number of cameras. In this example, the measurement area 101a is covered by three cameras 3a to 3c, so either three corrugated plates 101 for inspection are installed, or the installation positions of the corrugated plates 101 for inspection are shifted and the measurement area 101a is covered three times. It is necessary to carry out an inspection.

It is obvious that it requires a large amount of man-hours and effort to arrange a plurality of heavy inspection corrugated plates 101 at desired positions within the measurement area 101a with sufficient accuracy or multiple times.

In the inspection method of the planar shape measuring system of the comparative example, the planar shape measuring device 120 has the inspection result display section 28, and the data calculated and output by the surface coordinate conversion section 22 is displayed via the inspection result display section 28. output to a display device, etc.

The inspection result display section 28 not only performs data conversion for displaying data on a display device, but also can calculate and output the wave height, wave pitch, etc. of the inspection corrugated plate 101.

FIG. 6 is an example of an inspection screen output by the inspection method of the planar shape measuring system of the comparative example.
As shown in FIG. 6, in the inspection method of the comparative example, the measurement result of the surface of the inspection corrugated plate 101 can be displayed on the inspection screen 150 as surface height data. Therefore, when it is known in advance that there is no hardware abnormality in the projector 2 or the imaging device 3, when it is recognized that there is an abnormality in the data output to the inspection screen 150, the planar shape measuring device 120 This makes it possible to assume that there is an abnormality.

However, even if there is no hardware abnormality in the projector 2 or the imaging device 3, if the exposure amount, etc. of the imaging device 3 is not appropriate, the acquired image data may not be properly processed. is possible. Even when the acquired image data cannot be appropriately image-processed, an abnormal value may be output to the inspection screen 150.

In the inspection device 10 of the planar shape measurement system according to the embodiment, an inspection jig 1 that generates a deflection that can be detected with measurement accuracy is used instead of the inspection corrugated plate 101. The inspection jig 1 is a flat plate, and can have a width spanning the measurement area 1a. Therefore, the installation work of the inspection jig 1 in the measurement area 1a is completed by installing one inspection jig 1 once. Therefore, the number of man-hours and labor required for installing the inspection jig 1 can be significantly reduced.

Furthermore, the inspection jig 1 can be used to determine the validity of surface height data by comparing the measured deflection with a reference value.

Since the inspection device 10 includes an inspection image recording unit 12 connected to the imaging device 3, by displaying image data for each camera, it is possible to check whether there is an abnormality in the image data. The presence or absence of abnormalities in image data is not limited to obvious ones such as image defects, but by visually comparing with past image data, it becomes possible to discover minute abnormalities and signs of abnormalities.

The inspection image recording unit 12 performs image processing on image data for each camera, thereby making it possible to discover finer abnormalities, signs of abnormalities, etc. that are difficult to see visually by an operator.

The inspection device 10 is equipped with an inspection determination unit 14 that outputs data for determining the validity of measurement based on the surface height data of the inspection jig 1 output by the planar shape measuring device 20. , it is possible to easily determine whether there is an abnormality in the planar shape measuring device 20.

The inspection determination unit 14 calculates the effective rate of surface height data and the effective rate of deviation based on the reflected images of two slit-shaped lights, thereby detecting abnormalities in coordinate units within one image data that are difficult to visually observe. It becomes possible to detect the presence or absence of a substance at the measurement limit level.

The inspection device 10 includes an inspection result display section 16, and can convert the results calculated and determined by the inspection determination section 14 into data that can be appropriately displayed and output the data.

The inspection result display section 16 can also graphically display surface height data based on the reflected image of the slit-shaped light output by the planar shape measuring device 20 over the C direction. In addition, the inspection result display section 16 can also display the deviation data of the surface height data in a time-series manner in a graph. Therefore, it is possible to easily detect the presence or absence of an abnormality in the surface coordinate conversion processing or surface shape map reproduction processing of the planar shape measuring device 20.

Each component of the inspection device 10 may be configured with hardware or software, or may be realized by appropriately combining hardware and software. When the inspection device 10 is configured with software, for example, an arithmetic processing circuit may sequentially execute a program stored in a storage device such as a computer device or a programmable logic controller. Each component of the inspection device 10 can be implemented by one or more steps of a program.

According to the embodiment described above, it is possible to realize an inspection device for a planar shape measuring system that can easily inspect the planar shape measuring system.

Although several embodiments of the present invention have been described above, these embodiments are presented as examples and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, substitutions, and changes can be made without departing from the gist of the invention. These embodiments and their modifications are included within the scope and gist of the invention, as well as within the scope of the claimed invention and its equivalents. Further, each of the embodiments described above can be implemented in combination with each other.

1 inspection jig, 2 light projection device, 3 imaging device, 10 inspection device, 12 inspection image recording section, 14 inspection judgment section, 16 inspection result display section, 20 planar shape measuring device, 22 surface coordinate conversion section, 24 unevenness Shape calculation section, 26 Measurement result display section

Claims (5)

When the object to be measured is a steel plate, two lines are provided on the surface of the object to be measured within a measurement area provided on a plane including a first direction, which is the conveyance direction of the steel plate, and a second direction orthogonal to the first direction. a light projector provided to emit parallel slit-shaped light perpendicular to the first direction;
an imaging device configured to image the entire surface of the object to be measured within the measurement area from an upstream diagonal direction or a downstream diagonal direction of the first direction;
The bright lines corresponding to each of the two parallel slit-shaped lights of the reflection image data of the surface of the object to be measured captured by the imaging device are connected to the coordinates of the second direction in the first direction. and converts it into coordinate data in a third direction perpendicular to the second direction and outputs it as first surface height data of the object to be measured, and calculates the deviation of the first surface height data for each bright line. a planar shape measuring device that outputs second surface height data with reduced temporal fluctuations of the reflection image data based on the data;
An inspection device for a planar shape measurement system comprising:
inspection image recording means for recording and outputting the reflection image data together with the acquisition date and time;
Inspection determination means for outputting determination data for determining the inspection result of the planar shape measuring system based on the data output by the planar shape measuring device;
Equipped with
The object to be measured is a plate material having a length spanning the length of the measurement area in the second direction and having a flat surface, and when the object is stationary and installed in the measurement area, the planar shape measurement can be performed. It is an inspection jig installed to produce a deflection due to its own weight that can be detected by the measurement accuracy of the system,
In the inspection device of the planar shape measuring system, the determination data includes the amount of deflection of the inspection jig calculated and output by the planar shape measuring device. The image recording means has an image processing calculation function of reflection image data of the two parallel slit-shaped lights,
2. The inspection device for a planar shape measuring system according to claim 1, wherein the image processing calculation function calculates and outputs brightness data of the reflected image data. The inspection determination means includes:
determining whether the data of the first surface height in the second direction is within a predetermined range and calculating the number of coordinates within the predetermined range;
The plane according to claim 1 or 2, wherein it is determined whether the deviation data in the second direction is within a predetermined range, the number of coordinates within the predetermined range is calculated, and the result is output as the determination data. Inspection device for shape measurement system. Displaying data representing the shape of the object to be measured over the second direction based on the first surface height data;
The apparatus further includes inspection result display means for converting and outputting data based on the data of the second surface height in the second direction so as to display data of a pseudo two-dimensional surface shape of the object to be measured. An inspection device for a planar shape measuring system according to any one of claims 1 to 3. The inspection determination means may compare the amount of deflection of the inspection jig with a preset reference value, or compare the amount of deflection of the inspection jig with a previously measured deflection amount. The inspection device for a planar shape measuring system according to any one of claims 1 to 4, which allows selection of the following.

Images