CN115574725B - Steel plate size measurement method and system based on line structured light - Google Patents
Steel plate size measurement method and system based on line structured light Download PDFInfo
- Publication number
- CN115574725B CN115574725B CN202211568456.9A CN202211568456A CN115574725B CN 115574725 B CN115574725 B CN 115574725B CN 202211568456 A CN202211568456 A CN 202211568456A CN 115574725 B CN115574725 B CN 115574725B
- Authority
- CN
- China
- Prior art keywords
- steel plate
- line
- structure light
- line structure
- image
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
- 229910000831 Steel Inorganic materials 0.000 title claims abstract description 169
- 239000010959 steel Substances 0.000 title claims abstract description 169
- 238000000691 measurement method Methods 0.000 title description 5
- 238000000034 method Methods 0.000 claims abstract description 53
- 230000002159 abnormal effect Effects 0.000 claims description 12
- 238000000605 extraction Methods 0.000 claims description 8
- 238000001514 detection method Methods 0.000 claims description 3
- 238000009413 insulation Methods 0.000 claims description 3
- 238000004513 sizing Methods 0.000 claims 1
- 238000005259 measurement Methods 0.000 description 15
- 238000010586 diagram Methods 0.000 description 6
- 230000011218 segmentation Effects 0.000 description 2
- 230000006978 adaptation Effects 0.000 description 1
- 238000004364 calculation method Methods 0.000 description 1
- 230000001419 dependent effect Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000005286 illumination Methods 0.000 description 1
- 238000003384 imaging method Methods 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 239000011159 matrix material Substances 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 230000003287 optical effect Effects 0.000 description 1
- BULVZWIRKLYCBC-UHFFFAOYSA-N phorate Chemical compound CCOP(=S)(OCC)SCSCC BULVZWIRKLYCBC-UHFFFAOYSA-N 0.000 description 1
- 238000002310 reflectometry Methods 0.000 description 1
- 238000005096 rolling process Methods 0.000 description 1
Images
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
- G01B11/00—Measuring arrangements characterised by the use of optical techniques
- G01B11/002—Measuring arrangements characterised by the use of optical techniques for measuring two or more coordinates
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
- G01B11/00—Measuring arrangements characterised by the use of optical techniques
- G01B11/02—Measuring arrangements characterised by the use of optical techniques for measuring length, width or thickness
- G01B11/022—Measuring arrangements characterised by the use of optical techniques for measuring length, width or thickness by means of tv-camera scanning
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P90/00—Enabling technologies with a potential contribution to greenhouse gas [GHG] emissions mitigation
- Y02P90/30—Computing systems specially adapted for manufacturing
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Length Measuring Devices By Optical Means (AREA)
Abstract
The application provides a steel plate dimension measuring method and system based on line structured light, wherein the steel plate dimension measuring method comprises the following steps: acquiring the inclination angle and the plate head of a steel plate to be tested; according to the inclination angle and the plate head, adjusting line structure light to an initial scanning position; the initial scanning position is in front of the plate head and is not on the steel plate to be detected; moving the line structure light at a constant speed according to a preset speed until the line structure light scans to the tail of the steel plate to be tested, marking the first time when the line structure light scans to the head, and marking the second time when the line structure light scans to the tail; acquiring a scanning image group of a steel plate to be tested; the scanning image group comprises each frame of image in the line structure light scanning process; extracting the width of the steel plate to be detected from the scanning image group; and determining the length of the steel plate to be detected according to the preset speed, the first time and the second time. Thus, the reinforced line structure light is used for scanning the steel plate to be measured, the central line of the line structure light is extracted, and the length and the width of the steel plate to be measured are accurately measured according to the central line.
Description
Technical Field
The application relates to the field of steel plate production, in particular to a steel plate dimension measuring method and system based on line structured light.
Background
The steel plate is an important product produced by a plate rolling mill according to preset dimensions, and the dimension measurement is required to be carried out on the produced steel plate in order to ensure the quality.
Board mills typically use manual methods for dimensional measurement. Referring to fig. 1, a schematic diagram of prior art steel plate dimension measurement is shown. As can be seen from fig. 1, in the prior art, two operators are required to stand at two ends of the steel plate to be measured, and the tape measure is pulled to measure. However, when the steel plate is measured, slight jitter and position inclination exist, which can lead to inaccurate measurement results, wherein the slight jitter can lead to larger numerical difference between front and rear measurement, and the position inclination can lead to that the measured side length of the steel plate is smaller than the actual side length.
Currently, line structured light is increasingly being used for dimensional measurement, however, line structured light is commonly used to measure local dimensions of small parts. For steel plates, especially medium thickness steel plates, a stronger light intensity and a longer linear light bar are often required. Therefore, the existing line structured light cannot measure the steel plate size.
Disclosure of Invention
The application provides a steel plate size measuring method and system based on line structured light, which can be used for solving the technical problem that the existing line structured light cannot measure the steel plate size.
In a first aspect, the present application provides a method for measuring a size of a steel sheet based on line structured light, the method comprising:
acquiring the inclination angle and the plate head of a steel plate to be tested;
according to the inclination angle and the plate head, adjusting line structured light to an initial scanning position; the initial scanning position is in front of the plate head and is not on the steel plate to be detected;
the line structure light is moved at a constant speed according to a preset speed until the line structure light is scanned to the tail of the steel plate to be tested, the first time when the line structure light is scanned to the plate head is marked, and the second time when the line structure light is scanned to the tail of the steel plate to be tested is marked; the line structure light moves from the initial scanning position to the board head until scanning to the board tail is stopped;
acquiring a scanning image group of the steel plate to be tested; the scanning image group comprises each frame of image in the line structure light scanning process;
extracting the width of the steel plate to be detected from the scanning image group;
and determining the length of the steel plate to be detected according to the preset speed, the first time and the second time.
In an implementation manner of the first aspect, before the obtaining the inclination angle and the head of the steel sheet to be measured, the steel sheet dimension measurement method further includes:
detecting whether a bit signal is sent out; the in-place signal is used for indicating that the steel plate to be measured reaches a measuring station;
if the in-place signal is sent out, the step is executed to acquire the inclination angle and the head of the steel plate to be detected;
if the in-place signal is not issued, continuing to wait for the in-place signal.
In an implementation manner of the first aspect, the adjusting the line structured light to the initial scanning position according to the inclination angle and the board head includes:
according to the inclination angle and the plate head, adjusting the line structured light to be parallel to the edge of the plate head;
the line structured light is translated to the initial scan position.
In an implementation manner of the first aspect, the extracting the width of the steel sheet to be measured from the scan image set includes:
extracting a central line of line structured light from each frame of image;
calibrating the center line to obtain the width of the steel plate in each frame of image;
removing abnormal values of the width of the steel plate in all the images to obtain the mode of the residual width;
and determining the mode as the width of the steel plate to be detected.
In an implementation manner of the first aspect, the extracting a line structure light center line from each frame of image includes:
extracting the centerline of the line structured light from each frame of image according to the following formula:
wherein ,f（x，y) The line structure light stripe image is within%x，y) Gray scale atThe value of the sum of the values,Tthe threshold value for the stripe extraction,g（u，v) Is extracted at the following stageu，v) Gray value at, andu＝x－w 0 ，v＝y－h 0 ，w 0 for the number of offset columns in the image,h 0 offset number of lines in the image;
optimizing the centerline according to the following formula:
wherein ,g（u，v) For the stripe region to be initially extracted,h（i，j) To optimize the stripe areai，j) Gray value at, andi=u-w 1 ，j=v-h 1 ，w 1 ，h 1 the number of columns and the number of rows, respectively, of the stripe regions.
In an implementation manner of the first aspect, the calibrating the center line to obtain the width of the steel plate in each frame of image includes:
calibrating camera parameters according to the following formula:
calibrating the planar parameters of the line structured light according to the following formula:
wherein ,（x i ，y i ，z i ) Calibrating the coordinates of the stripes on the board under the camera coordinate system for the checkerboard,nis the number of stripe points for not in a straight line.
In an implementation manner of the first aspect, after the removing the abnormal values of the widths of the steel plates in all the images, obtaining a mode of the remaining width includes:
the mode of the remaining width is obtained according to the following formula:
wherein ,（u，v) Is the center line of #X c ,Y c ,Z c ) Is the unique spatial point corresponding to the point on the image under the camera coordinate system.
In an implementation manner of the first aspect, the determining the length of the steel plate to be measured according to the preset speed, the first time and the second time includes:
determining the length of the steel plate to be tested according to the following formula:
wherein ,Lfor the length of the steel sheet to be measured,Vfor the said preset speed of the vehicle,t 0 for the first time period in question,t 1 is the second time.
In a second aspect, the present application provides a line structured light-based steel sheet dimension measurement system for performing the line structured light-based steel sheet dimension measurement method of the first aspect and various realizations, the steel sheet dimension measurement system comprising:
the actuating mechanism module comprises a servo motor unit, a switch and a trigger signal unit and is used for executing the control of the starting and closing of the steel plate size measuring system;
the object in-place detection module is used for executing the following steps:
detecting whether an in-place signal is sent out or not before the inclination angle and the head of the steel plate to be detected are acquired;
the structure light width measuring module is used for executing the following steps:
acquiring the inclination angle and the plate head of a steel plate to be tested;
according to the inclination angle and the plate head, adjusting line structured light to an initial scanning position; the initial scanning position is in front of the plate head and is not on the steel plate to be detected;
the line structure light is moved at a constant speed according to a preset speed until the line structure light is scanned to the tail of the steel plate to be tested, the first time when the line structure light is scanned to the plate head is marked, and the second time when the line structure light is scanned to the tail of the steel plate to be tested is marked; the line structure light moves from the initial scanning position to the board head until scanning to the board tail is stopped;
acquiring a scanning image group of the steel plate to be tested; the scanning image group comprises each frame of image in the line structure light scanning process;
extracting the width of the steel plate to be detected from the scanning image group;
the structured light length measuring module is used for executing the following steps:
and determining the length of the steel plate to be detected according to the preset speed, the first time and the second time.
In one implementation manner of the second aspect, the steel plate dimension measurement system further includes a hardware structure, where the hardware structure includes:
a moving guide roller, and a measuring device arranged on the moving guide roller; the measuring device can move along the moving guide roller;
the measuring device includes:
the industrial camera is provided with a lens, and the lens is used for acquiring the scanning image group;
the line structure light emitter is used for emitting line structure light;
and the heat insulation and dissipation device is arranged at the tail ends of the industrial camera and the line structure light emitter and is used for keeping the temperature balance of the industrial camera and the line structure light emitter.
According to the technical scheme, the application provides a steel plate dimension measuring method and system based on line structured light, wherein the steel plate dimension measuring method comprises the following steps: acquiring the inclination angle and the plate head of a steel plate to be tested; according to the inclination angle and the plate head, adjusting line structured light to an initial scanning position; the initial scanning position is in front of the plate head and is not on the steel plate to be detected; the line structure light is moved at a constant speed according to a preset speed until the line structure light is scanned to the tail of the steel plate to be tested, the first time when the line structure light is scanned to the plate head is marked, and the second time when the line structure light is scanned to the tail of the steel plate to be tested is marked; the line structure light moves from the initial scanning position to the board head until scanning to the board tail is stopped; acquiring a scanning image group of the steel plate to be tested; the scanning image group comprises each frame of image in the line structure light scanning process; extracting the width of the steel plate to be detected from the scanning image group; and determining the length of the steel plate to be detected according to the preset speed, the first time and the second time.
Thus, the reinforced line structure light is used for scanning the steel plate to be tested, the central line of the line structure light is extracted, and the length and the width of the steel plate to be tested are accurately measured according to the central line.
Drawings
In order to more clearly illustrate the technical solutions of the present application, the drawings that are needed in the embodiments will be briefly described below, and it will be obvious to those skilled in the art that other drawings can be obtained from these drawings without inventive effort.
FIG. 1 is a schematic diagram of a prior art steel plate dimension measurement;
FIG. 2 is a schematic diagram of a line structured light measurement principle;
FIG. 3 is a schematic hardware diagram of a steel plate dimension measurement system based on a line structured light steel plate dimension measurement method provided in the present application;
FIG. 4 is a schematic flow chart of a method for measuring the dimensions of a steel plate based on line structured light;
fig. 5 is a schematic drawing showing the extraction of the center line of line structured light based on the method for measuring the size of steel plate by line structured light.
In fig. 3:
the device comprises a moving guide roller 1, a measuring device 2, an industrial camera 21, a lens 22, a line structure light emitter 23, a heat insulation and dissipation device 24, a portal frame 3 and a steel plate to be measured 4.
Detailed Description
For the purpose of making the objects, technical solutions and advantages of the present application more apparent, the embodiments of the present application will be described in further detail below with reference to the accompanying drawings.
The terminology used in the following embodiments is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. As used in the specification and the appended claims, the singular forms "a," "an," "the," and "the" are intended to include, for example, "one or more" such forms of expression, unless the context clearly indicates to the contrary. It should also be understood that in the various embodiments herein below, "at least one", "one" or "a plurality" means one, two or more, and "a plurality" means two or more. The term "and/or" is used to describe an association relationship of associated objects, meaning that there may be three relationships; for example, a and/or B may represent: a alone, a and B together, and B alone, wherein A, B may be singular or plural. The character "/" generally indicates that the context-dependent object is an "or" relationship.
Reference in the specification to "one embodiment" or "some embodiments" or the like means that a particular feature, structure, or characteristic described in connection with the embodiment is included in one or more embodiments of the application. Thus, appearances of the phrases "in one embodiment," "in some embodiments," "in other embodiments," and the like in the specification are not necessarily all referring to the same embodiment, but mean "one or more but not all embodiments" unless expressly specified otherwise. The terms "comprising," "including," "having," and variations thereof mean "including but not limited to," unless expressly specified otherwise.
The following first describes the line structured light measurement principle applied in the embodiments of the present application:
referring to fig. 2, a schematic diagram of a line structured light measurement principle is shown;
as can be seen from fig. 2, the linear structured light emitted from the linear structured light emitter is converged and irradiated on the surface of the object to be measured, and then the scattered light is received by the lens and converged on the linear photoelectric element imaging chip. When the surface of the measured object is displaced, the object light spot is deviated from the original object surface, and the image light spot also moves correspondingly. For rectangular steel plates, the image spots are connected in light bars, and the dimensions of the object are measured according to the changes of the light bars.
The following describes the hardware structure of the present application for performing the steel plate dimension measuring method:
referring to fig. 3, a hardware structure diagram of a steel plate dimension measuring system based on a steel plate dimension measuring method of line structured light is provided.
As can be seen from fig. 3, the hardware structure of the steel plate dimension measuring system includes:
a moving guide roller 1, and a measuring device 2 provided on the moving guide roller 1; the measuring device 2 can move along the moving guide roller 1;
the measuring device 2 includes:
an industrial camera 21, wherein a lens 22 is arranged on the industrial camera 21, and the lens 22 is used for acquiring the scanning image group;
a line structure light emitter 23 for emitting line structure light;
a heat-insulating and heat-dissipating device 24, disposed at the tail ends of the industrial camera and the line-structured light emitter, for maintaining the temperature balance of the industrial camera and the line-structured light emitter;
in the actual use process, all the hardware structures can be arranged on the portal frame 3 and arranged above the steel plate 4 to be tested.
The first embodiment of the application discloses a method for measuring the size of a steel plate based on line structured light, and the method for measuring the size of the steel plate based on the line structured light disclosed in the first embodiment of the application is specifically described below with reference to the accompanying drawings.
Referring to fig. 4, a flow chart of a method for measuring a steel plate dimension based on line structured light is provided;
as can be seen from fig. 4, the method for measuring the dimension of the steel plate based on the line structured light according to the first embodiment of the present application includes:
in the embodiment of the present application, the acquisition of the inclination angle and the board head is completed by the industrial camera 21, the industrial camera 21 photographs, visually detects the inclination angle of the board head and the position of the board head, and sends an angle signal to the PLC (Programmable Logic Controller ).
102, adjusting line structured light to an initial scanning position according to the inclination angle and the plate head; the initial scanning position is in front of the plate head and is not on the steel plate to be detected;
in the embodiment of the present application, the step 102 includes:
step 201, according to the inclination angle and the board head, adjusting the line structured light to be parallel to the edge of the board head;
step 202, translating the line structured light to the initial scanning position.
In the embodiment of the present application, the PLC adjusts the scanning angle of the line structure light emitter 23 above the gantry 3 to be parallel to the line of the edge of the slab head of the steel slab to be measured.
At the bookIn the embodiment of the application, after the position of the board head detected visually is sent to the PLC, the PLC moves the line structure light emitter 23 to the initial scanning position, so as to ensure that the board head is kept in a uniform speed state when scanned, and the speed of uniform speed movement is preset. To ensure uniform speed, the speed of the conveyor belt is sent to the system at regular time, and the system records the first time when the line structured light falls on the edge line of the board headt 0 And a second time when the line structured light falls on the plate tail edge linet 1 。
104, acquiring a scanning image group of the steel plate to be tested; the scanning image group comprises each frame of image in the line structure light scanning process.
in the present embodiment, in step 105, the industrial camera 21 records each frame of image in real time according to the line structured light measurement principle. The centerline of the line structured light is extracted from each frame image and its length width_pixel is calculated. And calibrating the central line, and converting the central line into the Width width_real of the steel plate. And removing abnormal values for width_real of each frame of image to calculate mode, and taking the Width of the bit plate blank.
Specifically, the step 105 includes:
step 502, extracting a central line of line structure light from each frame of image;
in the embodiment of the application, firstly, a threshold segmentation method is adopted to initially extract a stripe region from a stripe image, the stripe region is further optimized by combining a maximum value method, and then, a Hessian matrix method is adopted to extract a center point of the stripe region.
Referring to fig. 5, a schematic drawing is extracted from a center line of line structured light according to a method for measuring a steel plate size based on the line structured light;
as can be seen from fig. 5, since the line structured light is relatively thick, and errors are caused by directly measuring the line structured light, it is necessary to extract the center line of the line structured light, and the center line is relatively thin, and errors caused by the width of the line structured light are avoided. Thus, the step 502 includes:
step 5021, extracting a central line of line structure light from each frame of image, including:
step 5022, extracting the centerline of the line structured light from each frame of image according to the following formula:
wherein ,f（x，y) The line structure light stripe image is within%x，y) The gray value at which the color is to be changed,Tthe threshold value for the stripe extraction,g（u，v) Is extracted at the following stageu，v) Gray value at, andu＝x－w 0 ，v＝y－h 0 ，w 0 for the number of offset columns in the image,h 0 offset number of lines in the image;
in the embodiment of the present application, the industrial camera 21 is a camera with a filter, and in the acquired image, the gray level of the stripe part is significantly larger than the gray level of the other parts, so that the image stripe region is extracted by using a threshold segmentation method, as shown in formula (1).
Step 5023, optimizing the centerline according to the following formula:
wherein ,g（u，v) For the stripe region to be initially extracted,h（i，j) To optimize the stripe areai，j) Gray value at, andi=u-w 1 ，j=v-h 1 ，w 1 ，h 1 the number of columns and the number of rows, respectively, of the stripe regions.
In the embodiment of the present application, due to the characteristic of the line structured light, the gray value of the ideal stripe region should be gaussian, but the gray value of the extracted stripe region is abnormal due to the influence of external illumination and the influence of different reflectivity of the workpiece surface. In order to reduce the influence of abnormal values, a maximum value method is adopted to search the gray maximum value of the stripe region, and tau pixels are selected to optimize the stripe region near the gray maximum value coordinates, as shown in a formula (2).
Step 503, calibrating the center line, and obtaining the width of the steel plate in each frame of image;
in the embodiment of the application, since the camera parameter calibration can only obtain a ray passing through the line structure light center, in order to obtain the position of the line structure light on the surface of the workpiece under the camera coordinate system, not only the camera parameter is calibrated, but also the line structure light plane parameter is calibrated, and the point of the camera coordinate system is converted into the point of the line structure light coordinate system.
Specifically, in the embodiment of the present application, the step 503 includes:
step 5031, calibrating the camera parameters according to the following formula:
in the embodiment of the application, the camera is calibrated by adopting a Zhang Zhengyou calibration method based on a checkerboard to acquire the optical parameters of the camera and the external parameters relative to a world coordinate system. That is, the camera calibration parameters are solved by establishing the correspondence between the corner positions on the checkerboard calibration plate and the corner coordinates on the image plane, as shown in formula (3).
Step 5032, calibrating the planar parameters of the line structured light according to the following formula:
wherein ,（x i ，y i ，z i ) Calibrating the coordinates of the stripes on the board under the camera coordinate system for the checkerboard,nis the number of stripe points for not in a straight line.
In the embodiment of the application, according to the triangulation principle, the three-dimensional coordinates of the surface stripes of the workpiece are required to be obtained, and besides the calibration of camera parameters, the calibration of the line structure light plane method is also required. The method adopts a least square method to calibrate the linear structure light plane parameters, as shown in a formula (4).
Step 504, eliminating abnormal values of the width of the steel plate in all the images, and obtaining the mode of the residual width;
in the embodiment of the application, the line laser pixel length width_pixel is converted into the Width width_real of the steel plate according to the calibrated vision system. The specific method comprises the following steps: and calculating the unique spatial point relation corresponding to the point on the image under the camera coordinate system by combining the camera calibration parameter equation and the line structure light plane parameter equation. Then, all images are added into a queue buffer mechanism, abnormal values are removed through calculation of width_real of each frame of image in real time, and a stable mode is used as the Width of a bit plate blank.
Specifically, the step 504 includes:
the mode of the remaining width is obtained according to the following formula:
wherein ,（u，v) Is the center line of #X c ,Y c ,Z c ) Is the unique spatial point corresponding to the point on the image under the camera coordinate system.
In the embodiment of the application, the central line is extracted by the light stripe center extraction algorithmu，v) Calculating the unique spatial point corresponding to the point on the image under the camera coordinate system according to the formula (3) and the formula (4)X c ,Y c ,Z c ) As shown in equation (5).
And 505, determining the mode as the width of the steel plate to be tested.
And step 106, determining the length of the steel plate to be detected according to the preset speed, the first time and the second time.
The step 106 includes:
determining the length of the steel plate to be tested according to the following formula:
wherein ,Lfor the length of the steel sheet to be measured,Vfor the said preset speed of the vehicle,t 0 for the first time period in question,t 1 is the second time.
In the embodiment of the application, when the line structure light scans to the plate tail edge line, the frame is identified, and the current time point is recordedt 1 。
In order to make the measured length more accurate, the real-time speed information sent by the PLC is stored in a queue, data processing is carried out, the abnormal value of the average speed is removed, and the weight of all the average speeds is calculatedV Real world . Using the actual average speed of movement V of the mobile device Real world Line-mixing structure light scanning object timet 1 -t 0 ) Calculating the length of the medium plate as shown in (7)L。
L=(t 1 -t 0 )×V Real world （7）
wherein ,Lfor the length of the steel sheet to be measured,V real world For the actual average speed of movement to be described,t 0 for the first time period in question,t 1 is the second time.
According to the technical scheme, the application provides a steel plate dimension measuring method and system based on line structured light, wherein the steel plate dimension measuring method comprises the following steps: acquiring the inclination angle and the plate head of a steel plate to be tested; according to the inclination angle and the plate head, adjusting line structured light to an initial scanning position; the initial scanning position is in front of the plate head and is not on the steel plate to be detected; the line structure light is moved at a constant speed according to a preset speed until the line structure light is scanned to the tail of the steel plate to be tested, the first time when the line structure light is scanned to the plate head is marked, and the second time when the line structure light is scanned to the tail of the steel plate to be tested is marked; the line structure light moves from the initial scanning position to the board head until scanning to the board tail is stopped; acquiring a scanning image group of the steel plate to be tested; the scanning image group comprises each frame of image in the line structure light scanning process; extracting the width of the steel plate to be detected from the scanning image group; and determining the length of the steel plate to be detected according to the preset speed, the first time and the second time.
Thus, the reinforced line structure light is used for scanning the steel plate to be tested, the central line of the line structure light is extracted, and the length and the width of the steel plate to be tested are accurately measured according to the central line.
Corresponding to the method for measuring the size of the steel plate based on the line structured light provided in the first embodiment of the present application, the second embodiment of the present application provides a system for measuring the size of the steel plate based on the line structured light, the system for measuring the size of the steel plate comprises:
the actuating mechanism module comprises a servo motor unit, a switch and a trigger signal unit and is used for executing the control of the starting and closing of the steel plate size measuring system;
the object in-place detection module is used for executing the following steps:
detecting whether an in-place signal is sent out or not before the inclination angle and the head of the steel plate to be detected are acquired;
the structure light width measuring module is used for executing the following steps:
acquiring the inclination angle and the plate head of a steel plate to be tested;
according to the inclination angle and the plate head, adjusting line structured light to an initial scanning position; the initial scanning position is in front of the plate head and is not on the steel plate to be detected;
the line structure light is moved at a constant speed according to a preset speed until the line structure light is scanned to the tail of the steel plate to be tested, the first time when the line structure light is scanned to the plate head is marked, and the second time when the line structure light is scanned to the tail of the steel plate to be tested is marked; the line structure light moves from the initial scanning position to the board head until scanning to the board tail is stopped;
acquiring a scanning image group of the steel plate to be tested; the scanning image group comprises each frame of image in the line structure light scanning process;
extracting the width of the steel plate to be detected from the scanning image group;
the structured light length measuring module is used for executing the following steps:
and determining the length of the steel plate to be detected according to the preset speed, the first time and the second time.
The effects of the above device in executing the method can be referred to the description of the above method, and will not be repeated here.
Other embodiments of the invention will be apparent to those skilled in the art from consideration of the specification and practice of the invention disclosed herein. This application is intended to cover any variations, uses, or adaptations of the invention following, in general, the principles of the invention and including such departures from the present disclosure as come within known or customary practice within the art to which the invention pertains; it is intended that the specification and examples be considered as exemplary only, with a true scope and spirit of the invention being indicated by the following claims.
It is to be understood that the invention is not limited to the precise arrangements and instrumentalities shown in the drawings, which have been described above, and that various modifications and changes may be made without departing from the scope thereof; the scope of the invention is limited only by the appended claims.
Claims (7)
1. A method for measuring the size of a steel plate based on line structured light, characterized in that the method comprises the following steps:
acquiring the inclination angle and the plate head of a steel plate to be tested;
according to the inclination angle and the plate head, adjusting line structured light to an initial scanning position; the initial scanning position is in front of the plate head and is not on the steel plate to be detected;
the line structure light is moved at a constant speed according to a preset speed until the line structure light is scanned to the tail of the steel plate to be tested, the first time when the line structure light is scanned to the plate head is marked, and the second time when the line structure light is scanned to the tail of the steel plate to be tested is marked; the line structure light moves from the initial scanning position to the board head until scanning to the board tail is stopped;
acquiring a scanning image group of the steel plate to be tested; the scanning image group comprises each frame of image in the line structure light scanning process;
extracting the width of the steel plate to be detected from the scanning image group;
determining the length of the steel plate to be detected according to the preset speed, the first time and the second time;
the extracting the width of the steel plate to be detected from the scanning image group comprises the following steps:
extracting a central line of line structured light from each frame of image;
calibrating the center line to obtain the width of the steel plate in each frame of image;
removing abnormal values of the width of the steel plate in all the images to obtain the mode of the residual width;
determining the mode as the width of the steel plate to be detected;
the extraction of the center line of the line structure light from each frame of image comprises the following steps:
extracting the centerline of the line structured light from each frame of image according to the following formula:
wherein ,f（x，y) The line structure light stripe image is within%x，y) The gray value at which the color is to be changed,Tthe threshold value for the stripe extraction,g（u，v) Is extracted at the following stageu，v) Gray value at, andu＝x－w 0 ，v＝y－h 0 ，w 0 for the number of offset columns in the image,h 0 offset number of lines in the image;
optimizing the centerline according to the following formula:
wherein ,g（u，v) For the stripe region to be initially extracted,h（i，j) To optimize the stripe areai，j) Gray value at, andi=u-w 1 ，j=v-h 1 ，w 1 ，h 1 column number and row number of the stripe area offset respectively;
after eliminating abnormal values of the width of the steel plate in all the images, obtaining the mode of the residual width, wherein the method comprises the following steps:
the mode of the remaining width is obtained according to the following formula:
wherein ,（u，v) Is the center line of #X c ,Y c ,Z c ) Is the unique spatial point corresponding to the point on the image under the camera coordinate system.
2. The method for measuring the dimension of a steel plate based on line structured light according to claim 1, wherein before the step of obtaining the inclination angle and the head of the steel plate to be measured, the method further comprises:
detecting whether a bit signal is sent out; the in-place signal is used for indicating that the steel plate to be measured reaches a measuring station;
if the in-place signal is sent out, the step is executed to acquire the inclination angle and the head of the steel plate to be detected;
if the in-place signal is not issued, continuing to wait for the in-place signal.
3. The method for measuring the size of a steel plate based on line structured light according to claim 1, wherein said adjusting the line structured light to an initial scanning position according to the inclination angle and the plate head comprises:
according to the inclination angle and the plate head, adjusting the line structured light to be parallel to the edge of the plate head;
the line structured light is translated to the initial scan position.
4. The method for measuring the size of the steel plate based on the line structured light according to claim 1, wherein the step of calibrating the center line to obtain the width of the steel plate in each frame of image comprises the steps of:
calibrating camera parameters according to the following formula:
calibrating the planar parameters of the line structured light according to the following formula:
wherein ,（x i ，y i ，z i ) Calibrating the coordinates of the stripes on the board under the camera coordinate system for the checkerboard,nis the number of stripe points for not in a straight line.
5. The method for measuring the size of a steel sheet based on line structured light according to claim 1, wherein the determining the length of the steel sheet to be measured according to the preset speed, the first time and the second time comprises:
determining the length of the steel plate to be tested according to the following formula:
wherein ,Lfor the length of the steel sheet to be measured,Vfor the said preset speed of the vehicle,t 0 for the first time period in question,t 1 is the second time.
6. A line structured light based steel sheet dimension measuring system for performing a line structured light based steel sheet dimension measuring method according to any one of claims 1 to 5, said steel sheet dimension measuring system comprising:
the actuating mechanism module comprises a servo motor unit, a switch and a trigger signal unit and is used for executing the control of the starting and closing of the steel plate size measuring system;
the object in-place detection module is used for executing the following steps:
detecting whether an in-place signal is sent out or not before the inclination angle and the head of the steel plate to be detected are acquired;
the structure light width measuring module is used for executing the following steps:
acquiring the inclination angle and the plate head of a steel plate to be tested;
according to the inclination angle and the plate head, adjusting line structured light to an initial scanning position; the initial scanning position is in front of the plate head and is not on the steel plate to be detected;
the line structure light is moved at a constant speed according to a preset speed until the line structure light is scanned to the tail of the steel plate to be tested, the first time when the line structure light is scanned to the plate head is marked, and the second time when the line structure light is scanned to the tail of the steel plate to be tested is marked; the line structure light moves from the initial scanning position to the board head until scanning to the board tail is stopped;
acquiring a scanning image group of the steel plate to be tested; the scanning image group comprises each frame of image in the line structure light scanning process;
extracting the width of the steel plate to be detected from the scanning image group;
the structured light length measuring module is used for executing the following steps:
determining the length of the steel plate to be detected according to the preset speed, the first time and the second time;
the extracting the width of the steel plate to be detected from the scanning image group comprises the following steps:
extracting a central line of line structured light from each frame of image;
calibrating the center line to obtain the width of the steel plate in each frame of image;
removing abnormal values of the width of the steel plate in all the images to obtain the mode of the residual width;
determining the mode as the width of the steel plate to be detected;
the extraction of the center line of the line structure light from each frame of image comprises the following steps:
extracting the centerline of the line structured light from each frame of image according to the following formula:
wherein ,f（x，y) The line structure light stripe image is within%x，y) The gray value at which the color is to be changed,Tthe threshold value for the stripe extraction,g（u，v) Is extracted at the following stageu，v) Gray value at, andu＝x－w 0 ，v＝y－h 0 ，w 0 for the number of offset columns in the image,h 0 offset number of lines in the image;
optimizing the centerline according to the following formula:
wherein ,g（u，v) For the stripe region to be initially extracted,h（i，j) To optimize the stripe areai，j) Gray value at, andi=u-w 1 ，j=v-h 1 ，w 1 ，h 1 column number and row number of the stripe area offset respectively;
after eliminating abnormal values of the width of the steel plate in all the images, obtaining the mode of the residual width, wherein the method comprises the following steps:
the mode of the remaining width is obtained according to the following formula:
wherein ,（u，v) Is the center line of #X c ,Y c ,Z c ) Is the unique spatial point corresponding to the point on the image under the camera coordinate system.
7. The line structured light based steel sheet sizing system of claim 6, further comprising a hardware structure comprising:
a moving guide roller, and a measuring device arranged on the moving guide roller; the measuring device can move along the moving guide roller;
the measuring device includes:
the industrial camera is provided with a lens, and the lens is used for acquiring the scanning image group;
the line structure light emitter is used for emitting line structure light;
and the heat insulation and dissipation device is arranged at the tail ends of the industrial camera and the line structure light emitter and is used for keeping the temperature balance of the industrial camera and the line structure light emitter.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202211568456.9A CN115574725B (en) | 2022-12-08 | 2022-12-08 | Steel plate size measurement method and system based on line structured light |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202211568456.9A CN115574725B (en) | 2022-12-08 | 2022-12-08 | Steel plate size measurement method and system based on line structured light |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN115574725A CN115574725A (en) | 2023-01-06 |
| CN115574725B true CN115574725B (en) | 2023-04-25 |
Family
ID=84590613
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202211568456.9A Active CN115574725B (en) | 2022-12-08 | 2022-12-08 | Steel plate size measurement method and system based on line structured light |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN115574725B (en) |
Family Cites Families (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101329174A (en) * | 2007-12-23 | 2008-12-24 | 中国海洋大学 | Full-field visual self-scanning measurement device |
| CN107578464B (en) * | 2017-06-30 | 2021-01-29 | 长沙湘计海盾科技有限公司 | Conveyor belt workpiece three-dimensional contour measuring method based on line laser scanning |
| CN107764205B (en) * | 2017-11-06 | 2020-05-12 | 长安大学 | Three-dimensional detection device and detection method of weld seam morphology of high-frequency resistance welding based on line structured light scanning |
| CN108592816B (en) * | 2018-04-26 | 2020-05-26 | 上海交通大学 | A three-dimensional measurement device and method for large-scale surfaces |
| CN110617763A (en) * | 2019-07-04 | 2019-12-27 | 天津大学 | Rotating structure optical type H-shaped steel size measurement method |
| CN113375566B (en) * | 2021-06-09 | 2023-09-08 | 江苏中科贯微自动化科技有限公司 | Accurate measurement method and system for object size |
| CN113834445A (en) * | 2021-10-04 | 2021-12-24 | 东北大学 | Method for detecting sizes of slag and burr in casting blank flame cutting |
| CN115265371A (en) * | 2022-06-26 | 2022-11-01 | 太原科技大学 | An online real-time measurement method of steel plate based on line structured light |
-
2022
- 2022-12-08 CN CN202211568456.9A patent/CN115574725B/en active Active
Also Published As
| Publication number | Publication date |
|---|---|
| CN115574725A (en) | 2023-01-06 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN101526336B (en) | Calibration method of linear structured light three-dimensional visual sensor based on measuring blocks | |
| US11042146B2 (en) | Automated 360-degree dense point object inspection | |
| CN107578464B (en) | Conveyor belt workpiece three-dimensional contour measuring method based on line laser scanning | |
| CN114041168A (en) | Automated 360-degree dense point object inspection | |
| CN101365144B (en) | Adjustment and Calibration Method of Linear Array CCD Scanning Detection System | |
| JP5412829B2 (en) | Steel plate shape straightening device | |
| KR100323955B1 (en) | Bending Angle Detection Device, Linear Extraction Device Used in It, and Bending Angle Detection Position Setting Device | |
| CN111421001B (en) | Online accurate centering system of high-speed wire rod mill and centering method thereof | |
| CN108335286B (en) | Online weld joint forming visual detection method based on double-line structured light | |
| US12079980B2 (en) | System and method for measuring a surface in contoured glass sheets | |
| CN108592816B (en) | A three-dimensional measurement device and method for large-scale surfaces | |
| CN107462587B (en) | Precise visual inspection system and method for concave-convex mark defects of flexible IC substrate | |
| CN106018431A (en) | Solid wood plate surface crack detecting system and detecting method | |
| JP5245817B2 (en) | Steel plate shape measuring method and shape measuring device | |
| CN113074660B (en) | Surface shape measuring method for large-size transparent object | |
| EP3858626B1 (en) | Method and system for double-sided printing | |
| CN110116138A (en) | Hot steel plate length and lateral bending measurement method in a kind of operation of rolling | |
| CN113393509B (en) | Laser radar multipath compensation method | |
| CN113804696B (en) | Method for determining size and area of defect on surface of bar | |
| CN116922775A (en) | Printing abnormality detection method, 3D printer, and computer-readable storage medium | |
| CN115855955A (en) | Mold surface structure defect detection device and method based on multi-beam laser | |
| JP5136108B2 (en) | 3D shape measuring method and 3D shape measuring apparatus | |
| CN112381888A (en) | Dynamic compensation method for H-shaped steel cutting path | |
| CN115574725B (en) | Steel plate size measurement method and system based on line structured light | |
| JPH07239221A (en) | Bending angle detector and linear extracting device and device for setting bending angle detection position therefor |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |